■■Hi 

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ANATOMY  IN  A  NUTSHELL 


LAUGHLIN 


(Second  Edition.) 


Poor    Humanty. 


The  following  | try  was  found  in  the  pocketbook  of  the  lute  G.  H.  Laughlin. 

More  than  half  a  century  since  the  following  lines  were  found  in  the  Royal  College  of 
Surgeons,  London,  beside  a  skeleton,  remarkable  for  its  symmetry  of  form.  They  were  sub- 
sequently  published  in  the  London  Morning  Chronicle,  and  a  vain  effort  made  to  ascertain 

tuthor,  even  offering  a  reward  of  fifty  guineas. 


I. 

Behold  this  ruin!     'Twas  a  skull 
<  Mice  of  ethereal  spirit  full. 

This  narrow  cell  was  Life's  retreat, 
This  space  was  Thought's  mysterious  seat. 
\\  hat  beauteous  visions  filled  this  spot 
With  dreams  of  pleasures  long  forgot ! 

Nor  hope,  nor  joy,  nor  love,  nor  fear. 
Have  left  one  trace  of  record  here. 


II. 

Beneath  this  moulding  canopy 

(  dice  shone  the  bright  and  busy  eye. 

But  start  not  at  the  dismal  void! 

If  social  love  that  eye  emplox  >'d; 

If  with  no  lawless  fire  it  gleamed, 

Hut  through  the  dews  of  kindness  beamed, 

That  eye  shall  be  forever  bright 

When  sun  and  stars  are  sunk  in  night. 


111. 

Within  this  hollow  cavern  hung 
The  ready,  swift  and  tuneful  tongue. 
If  Falsehood's  honey  it  disdained. 
And  when  it  could  not  praise  was  chain* 
If  bold  in  Yin  lie's  cause  it  spoke, 

^  et  gentle  concord  never  broke 

Thai  silent  tongue  shall  plead  lor  thee, 

\\  hen  time  unveils  eternitv! 


[V. 

Say,  did  these  lingers  delve  the  mine, 
( )r  with  the  envied  ruby  shine? 
To  hew  the  rock  or  wear  t  he  gem, 
( 'an  little  now  avail  to  them. 
Hut  if  the  page  of  truth  they  sought, 
(  >r  comfort  to  the  mourner  brought — 
These  hands  a  richer  meed  shall  claim 
Than  all  who  wait  on  Weal  or  fame. 


Avails  it    whether  bare  01    shod, 
These  feet   the  path  of  duty  trod'.' 
If  from  the  bowers  of  ease  they  lied. 
To  seek  Affliction's  humble  shed; 
If  Grandeur's  guilty  bribe  they  Spurned, 
And  home  to  Virtue's  cot    returned 
These  feet    with   angel's   wings  shall   vie. 
And   tread   the  palace  of  the  skies. 

Anonymi  m  - 


ANATOMY   IN   A   NUTSHELL 


A  TREATISE  ON   HUMAN  ANATOMY 
IN   ITS  RELATION  TO  OSTEOPATHY 


WILLIAM  ROSS  LAUGHLIN,  M.  S.,  D.  0. 

PROFESSOR  OF  DESCRIPTIVE  ANATOMY,    NEUROLOGY  AXD  OSTEOPATHIC  TECHNIQUE 
IN  THE   AMERICAN  SCHOOL  OF  OSTEOPATHY,  KIRKSVILLE.  MO. 


IX  OXE  VOLUME. 
ILLUSTRATED  BY  TWO  HUNDRED  AND  NINETY  PLATES. 


KIRKSVILI.I 
WILLIAM  ROSS  LAUGHLIN,  M.S..  D.  0. 
611  East  Harrison  Street 
1905. 


QS  *f 

3' 


Copyright,  L905,  by  William  Rosa  Laughlin. 


\lii\.  n  ^  pb  l  < » M  l  •  IS1  i  ION 

PRESS  OF  in'  RN  \l.  PR]  \  I  im.  CO 

KIRKSVILLE,  MISSOURI 


TO 

fll>£  present  ano  former  Stuoents  of  Enatomp 

THIS  WORK 

IS  AFFECTIONATELY  DEDICATED 

BY 

THEIR  FELLOW  WORKER, 

THE  AUTHOR. 


(Qui  ram  prafirit,  deficit. 


List  of  Illustrations. 


Plate 

I. 

II. 

III. 

IV. 

V. 

VI. 

VII. 

VIII. 

IX. 

X. 

XI. 

XII. 

XIII. 

XIV. 

XV. 

XVI. 

XVII. 

XVIII. 

XIX. 
XX. 

XXI. 

XXII. 

XXIII. 

XXIV. 

XXV. 

XXVI. 

XXVII. 

XXVIII. 

XXIX. 

XXX. 

X  XXI. 

XXXII. 

XXXIII. 

XXXIV. 

XXXV. 

XXXVI. 

XXXVII. 

XX  XVIII. 

XXXIX. 

XL. 

XI. I. 

XLII. 

XLIII. 


Page 

The  Bony  Man is 

The  Muscular  Man 21 

Showing  the  Origin  and  Insertion  of  Biceps 2  1 

A  Transverse  Section  of  Spinal  Cord 25 

Posterior  Mew  of  the  Spinal  Cord 29 

Brachial  Plexus 81 

Nutrient  Arteries  of  Bones  of  the  Hand 33 

Relative  Position  of  Vessels  Above  and  Below  Diaphragm 30 

The  Fetal  Circulation  and  the  Adult  Circulation 39 

The  Left  Clavicle,  Inferior  Surface 41 

The  Left  Clavicle,  Superior  Surface 41 

The  Sterno-Clavicular  Articulation 43 

Acroinio-(  "lavicular  Articulation  and  Shoulder-Joint 44 

Muscles  of  Face  and  Triangles  of  Xeck 47 

External  ( >blique  Muscle  of  Abdomen  and  Numerous  *  >ther 

Structures 4!) 

Internal  ( >blique  Muscle  of  Abdomen,,  Numerous  ( >ther  St  ructures 51 

Transversalis  Muscle  of  Abdomen,  Numerous  Other  Structures 53 

Muscles  of  the  Back.  Superficial  Layers 57 

The  Hyoid  Bone 59 

The  Left  Scapula,  Posterior  Surface  or  Dorsum    63 

The  Left  Scapula.  Anterior  Surface  or  Venter 6  I 

The  Left  Humerus,  Posterior  View 

The  Left  Humerus,  Anterior  View 

The  Left  Radius  and  Ulna,  Posterior  View 

The  Left  Radius  and  Tina,  Anterior  View 

Bones  of  Left  Hand,  Posterior  View 

Bones  of  Left  Maud.  Anterior  View 

Showing  Quadrilateral  Space,  Struct  ures  Passing  Through  it 

Muscles  of  Left  Forearm      First  Layer — Anterior  View 

Muscles  of  Left  Forearm — Second  Layer     Anterior  View 

Muscles  of  Left  Forearm     Third  and  Fourth  Layers     Anterior 

View 

Muscles  of  the  Left  Forearm— Superficial  Layer     Posterior  View.    ... 

Muscles  of  t  he  Left  Forearm     Peep  Layer     Posterior  Vie\*    

The  Four  Dorsal  Interossei 

The  Three  Palmar  Interossi 

Showing  t  he  Cutaneous  Nerve  Supply  of  Upper  Extremity 

Lymphatics  and  Veins  of  I  he  Upper  Extremity     Superficial   1 

...     1 

1 


The  Elbow  Joint ,  External  View 

The  Elbow-Joint,  Internal  View 

The  Wrist-Joint ,  Posterior  View 1 

The  Wrist-Joint,  Anterior  View 1 

Showing  the  Synovial  Membranes  of  the  Wrisl 1 

Externa]  Mew  of  the  Left  [nnominate  Bone 1 

i\ 


1 17 
lis 
70 
71 

7:; 
74 

SO 

83 

86 

89 
90 
93 

'.il 
07 
00 

03 

in 
07 

us 

1  1 

2  I 


IS 


[.1ST  OF  ILLUSTRATIONS. 

Plate  Page 

XLIV.     Internal  View  <>f  Lefl  Innominate  Bone 127 

X  l.\  .     Posterior  View  of  Sacrum  and  Coccyx 130 

XL VI.     Anterior  View  <>l  Sacrum  and  Coccyx 133 

X  I. VI I       Anterior  and  Superior  View  of  Pelvis 136 

XLVIII.     Posterior  View  of  Lefl  Femur 139 

XLIX.     Anterior  View  of  Left  Femur 142 

I.      Posterior  View  of  Lefl  Tibia  and  Fibula 145 

LI.     Anterior  View  of  Lett  Tibia  and  Fibula 148 

Id  I.     Dorsum  of  Left  Fool 151 

I   III.       Plantar  Surface  of  Left  loot 155 

LIV.     Showing  the  I  >i  red  ion  of  Nutrient  Arteries  of  Bones  of  Fool 159 

LV.      Plant  'ii'  Fascia  and  First  Layer  of  Muscles  of  Foot 161 

LVI.  First  Layer  of  Muscles  of  the  Foot,  Also  Internal  and   External  Plan- 
tar Arteries 163 

LVII.       I.umliricale.-..  Internal  and  External  Plantar  Vessels  and  Nerves 165 

I.YI  1 1.     Accessorius  Mi  ode  and  Plantar  Vessels 167 

I. IX.     Flexor  Longus  Digitorum  Tendon  and  Four  Lumbricales 169 

I.X.      Third  Layer  of  Muscle-  of   Foot 171 

I. XL     The  Four  Dorsal  Interossei 173 

LXII.      The  Three  Plantar  Interossei 175 

I.X  1 1 1.      Lumbar,  Sacral  and  (  'occvyeal  Plexuses 177 

I.X  IV.      ( 'otninon.  Superficial  and  Profunda  Femoral  Arteries 179 

LXV.     Muscle-  in  ( (luteal  Region  and  Hack  of  Thigh 181 

LXVI.      Superficial  Lymphatic  Vessels  and  Veins  of  Leg 183 

LXV]  I.      External  or  Short  Saphenous  Vein 185 

LXVIII.      Anterior  View  of  Entire  Lower  Limb 187 

I.X  IX.      Showing  Arteries  and  Nerves  of  Hack  of  Leg 189 

LX  X.       Showing  Muscles  of  Hack  of  Ley; 191 

LXX  I.      Showing  Muscles  of  I  unci  and  Anterior  Part  of  the  Thigh 193 

LXXII.     The  Arteries  of  Entire  Lower  Extremity 195 

I.XXIII.     The  Diaphragm,  Psoas  Magnus  and  Parvus 197 

LXXIV.     The  Muscles  in  Front  oftheThigh 199 

LXXV.     Musclesin  Front  of  Ley 201 

LXXVI.     Arteries  and  Nerves  in  Front  of  Leg 203 

LXXVII.     Muscles  in  Hack  of  Ley  (Superficial  Layer)   205 

LXX  VIII.     Posterior  View  of  Entire  Leg 207 

LX  NIX.     Musclesol  Back  of  Leg  l  I  >eep  Layer) 209 

L.N  N.N.     Cutaneous  Nerve  Supply  of  the  Lower  Extremity 211 

I. XXX  I.     Cutaneous  Nerve  Supply  of  the  Plantar  Surface  of  the  Foot 213 

I.NNXII.     Ligaments  of  Hip-Joinl 215 

LXXXIII.     Ligamentum  Patella 217 

LXXXIV.     Posterior  Ligamenl  of  Knee. loin  t 219 

LXXXV.     Showing  ( !ondyles  and  Ligaments  of  Knee-Join1 .  Anterior  View 221 

LXXXVI.     Semilunar  Fibro-<  'art  i  la  ye  of  Knee-Joint 222 

LXXXVII.     Ligaments  oi  Ankle-External  View 223 

LXXXVIII.     Ligaments  of  Ankle     [nternalView 224 

I..N.N.NI.N       Forms  of  Club  Fool       226 

XC.     Showing  Great  Vessels  Belowthe  Diaphragm 228 

XCI.     Showing  Abdominal  Arota  and  its  Terminal   Branches 229 

XCII.     Anterior  View  of  Sternum 231 

XCIII.     Posterior  View  of  Sternum 233 

N<  TV.     Bones  of  the  Thorax 235 

XCV.     The  Atlas                                            237 

X('\  I.     Posterior  View  of  Axis                    239 

XCVII.     Anterior  View  of  Axis 241 


LIST    OF    ) ILLUSTRATIONS.  XI 

Plate  Page 

XCVIII.  The  Fifth  Cervical  Vertebra 243 

XCIX.  A  Dorsal  Vertebra  with  Long  Spine 245 

C.  A  Lumbar  Vertebra 247 

CI.  Veins  of  Spinal  Cord  and  Column  (Transverse  View) 249 

CII.  Veins  of  Spinal  ( '<>nl  and  Column  (Sagittal  View) 251 

CIII.  The  Spinal  Column 253 

CIV.  Ligaments  of  Spinal  Column .  .               255 

(A'.  Anterior  Mew  of  Cervical  Vertebrae                                                 257 

<  VI.  Posterior  View  of  Cervical  Vertebrae 259 

CVII.  The  Peculiar  1  tarsal  Vertebras 261 

CVTLT.  The  Second  and  Seventh  Ribs 263 

CIX.  Ligaments  of  Upper  Cervical  Vertebrae 265 

CX.  Muscles  of  Anterior  Cervical  Region 267 

CXI.  Muscles  of  Back  (Dee])  Layer) 269 

CXLT.  The  Posterior  Cervical  Plexus -'71 

CXIII.  The  Cervical  Plexus 27:1 

CXIY.  Thyroid  axis  and  Cords  of  Brachial  Plexus 27."> 

( 'XV.  Lymphatics  of  Neck  and  Face 277 

CXVL  The  External  Carotid  Artery 279 

CXVH.  The  Internal  Carotid  Artery 281 

(  Will.  The  Arteries  from  Arch  of  Aorta  to  Circle  of  Willis 283 

CXIX.  The  Cervical  Fascia 285 

CXX.  The  Trachea 287 

(XXL  The  Heart,  Thyroid  Claud,  and  Lungs  (Turned  Downward) 289 

CXXII.  Anterior  Mew  of  Lungs 290 

CXXIII.  Posterior  View  of  Lungs 291 

(  XXIV.  Showing  the  Capacity  of  the  Lungs 292 

( 'XXV.  Showing  Pleura-  and  Roof  of  the  Lungs 293 

CXXVL  Air  Cells  of  the  Lungs 294 

CXXVII.  A  Transverse  Section  of  the  Pleurae  Through  Root  of  Lungs 295 

(  XX  VIII.  Arch  of  Aorta  and  Heart 296 

('XXIX.  Showing  Circulation  of  the  Blood  Through  Heart 297 

CX XX.  Semilunar  Valve  (Aortic) 298 

<  WXXI.  The  Thoracic  Duct  and  Azygos  Veins 299 

CXXXII.  Thyroid  Gland  of  Fetus 300 

CXXXIII.  Thyroid  Cartilage  (Anterior  View) 301 

(XXXIV.  Eyoid  Bone/Thyroid  and  Cricoid  Cartilages  (Anterior  View) 302 

CXXXV.  Thyroid  ( 'artilage  (Posterior  View) 303 

CXXXVI.  Arytenoid  Cartilage  and  Epiglottis 304 

CXXXVII.  True  and  False  Vocal  Cords 305 

CXXXVIII.  Showing  the  Entire  Alimentary  Canal  and  Portal  Circulation 308 

(   XXX  IX.  Anterior  and  Posterior  Pi  Hal's  of  Fauces  and  ( 'artilages  of  Nose 310 

('XI..  The  Salivary  Glands 312 

(   XLI.  Showing  Muscles  of  the  Pharynx 314 

CXLII.  A  Sagittal  Section  of  Head  and  Neck  showing  Pharynx  316 

CXLIII.  The  Dorsum  of  the  Tongue 31«» 

CXLIV.  Circumvallate    Papilla- 321 

CXLV.  The  Extrinsic  Muscles  of  the  Tongue ;-'.: 

CXLVI  The  (Esophagus  and  Stomach 325 

CXLVII.  Showing  Viscera  Below  Diaphragm 321 

CXLVIII.  Showing  Blood  Supply  of  Stomach    328 

CXLIX.  Showing  Muscular <  'oats  and  Relations  of  Stomach     329 

('!..  Showing  Peritoneum     Closed  Sac 330 

CLE  Sagittal  Section  of  Trunk  Showing  Peritoneum. . .  •"•:;| 

CLII.     Relationsof  Liver 


Xll 


Plate 
CLIII. 

ci  l\ 

CLV. 

CLVI. 

CIA  II. 

CLVIII. 

CLIX. 

CLX. 

CI. XI. 

CLXII. 

CI. XIII. 

CI. XIV. 

CI. XV. 

CI.  XVI. 

CI. XVII. 

CI. XVIII. 

CLX  IX. 

CI.XX. 

CLXXI. 

CLXXII. 

CLXXIII. 

CI.WIN 

CLXXV. 

CLXXVI. 

CLXXVII. 

CLXXVIII. 

CI. XXIX. 

CI. XXX. 

CI. XXXI. 

CLXXXII. 

(I. XXXIII. 

CI. XXX  IV. 

CI. XXXV 

CLXXXVI. 

CLXXXVII. 

CI.XX.W  III. 

CI.  XXXIX. 

CXC. 

CXCI. 

CXCII. 

CXCIII. 

CXCIV. 

cxcv. 

CXCVI. 

CXCVII. 

CXCVIII. 

CXCIX. 

cr. 

CCI. 

ecu. 

OCIII. 

CCIV. 

cc\. 

CCVI. 

CCVII. 


LIST    OF     ILLUSTRATION'S. 

Page 

The  Superior  Surface  of  Liver 333 

The  [nferior  Surface  of  Liver 334 

The  Vessels  of  a  Lobule  of  Liver 335 

Showing  Blood  Supply  to  Small  Intestine 336 

Showing  Blood  Supply  to  Large  Intestine 337 

Showing  the  Vermiform  Appendix  and  Four  Forms  of  Caecum 33S 

[leo-Caecal  Valve 339 

A  Transverse  Section  of  the  Large  Intestine 34o 

The  Pancreas,  I  Juodenum,  and  Kidney 341 

Lobes  and  Fissures  of  Liver 342 

Showing  the  Four  Coats  of  Stomach  and  Pyloric  ( >ririee 343 

Showing  ( terminal  Area 344 

Showing  1  >evelopmen1  of  t  lie  Sympathetic  Nerve 345 

A  Horizontal  Section  of  Vertebrate  Brain 346 

A  Sagittal  Section  of  Vertebrate  Brain 347 

A  Sagittal  Section  of  the  Brain 348 

A  Coronal  Section  Through  Anterior  Horn  of  Lateral  Ventricle 340 

A  Coronal  Section  Through  Middle  Commissure  of  Brain 350 

A  ( 'oronal  Section  Through  Posterior  Horn  of  Laterial  Ventricles 351 

A  ( 'ast  of  Ventricles  of  the  Brain 352 

The  Circle  of  Willis 353 

Showing  Blood  Supply  on  External  Surface  of  Brain 354 

Showing  Distribution  of  Middle  cerebral  Artery 355 

Showing  Blood  Supply  on  Mesial  (Sagittal  Surface)  of  Brain 356 

Showing  Blood  Supply  at  Base  of  Brain 357 

Showing  Falx  Cerebri,  etc 358 

Sinuses  at  the  Base  of  Brain    359 

Sagittal  Section  of  Brain  Showing  Third  and  Fourth  Ventricles 360 

Sagittal  Section  of  BrainShowing  Fibers 361 

Sagittal  Section  of  Brain  Showing  Centers  of  Smell  and  Taste 362 

Location  of  Centers  in  Brain 363 

A  Sagittal  Section  of  the  Brain 364 

Showing  Long  and  Short  Association  Fibers  of  the  Brain 365 

A  Horizontal  Section  of  the  Brain 366 

Showing  Superficial  I  origin  of  Cranial  Nerves 367 

Superior  View  of  t  he  ( lerebellum 368 

Inferior  View  of  t  he  Cerebellum 369 

Showing  t  lie  Writing  Center   in  the  Brain 370 

Anterior  View  of  <  'auda  Equina 371 

Showing  Dura  Mater,  Arachnoid  and  Piamater 372 

Transverse  Section  of  the  Con  1  at  Different  Levels 373 

Transverse  Sect  ions  of  t  he  ( !ord  Shewing  Tracts,  1  hseases,  etc 374 

Vena  Azygos  Major,  Abdominal  Aorta  and  Sympathetic  Nerve 375 

Anterior  View  of  Sympathetic  Nerve  and  Spinal  Cord 377 

Side  View  of  S\  mpat  hetic  System 379 

Showing  Kami  ( !ommunicantes 380 

The  (  Ufactory  or  First  Cranial  Nerve 381 

The  Layers  of  Retina    382 

Blood  Supply  to  Eye-Ball 383 

Showing   Venae  Vorticosae 384 

I  distribution  of  <  (phthalmic  Artery 386 

( Iptical  Axis  and  Visual  Line 388 

Nasal   1  >UC1 .  <  lonjunctiva  and  Lachrymal  ( iland 390 

The  Muscles  of  the  I  Irbital  Region 391 

Showing  Directions  that  Muscles  of  Eve-Ball  move  Eve 392 


Plate 
CCVIII. 

CCIX. 

ccx. 

('('XI. 

('('XII. 

('('XIII. 

CCXIV. 

ccxv. 

CCXVI. 

CCXVII. 

CCXVIII. 

CCX  IX. 

ccxx. 

CCXXI. 

CCXX  1 1. 

CCXXIII. 

(  (XXIV. 

(  (XXV. 

CCXXVI. 

CCXX  VI  I. 

((  XXVIII. 

CCXXIX. 

CCX  XX. 

CCXXXI. 

CCXXXII. 

CCXXXIII. 

CCXXXIV. 

(  (XXXV. 

CCXXXVI. 

('(  XXXVII. 

C(  XXXVIII. 

CCXXXIX. 

CCX  I.. 

CCXLI. 

CCXLII. 

CCXLIII. 

CCX  I. IV. 

CCXLV. 

CCXLVI. 

CCXLVII. 

CCXLVIII. 

CCXLIX. 

CCL. 

CCLI. 

CCLII. 

CCLIII. 

CCLIV. 

CCLV. 

CCLVI. 

CCLVII, 

CCLVIII. 

CCLIX. 

CCLX. 

CCLXI. 

CCLXII. 


LIST    OF    ILLUSTRATION--,  xill 

Page 

Showing  Refraction  of  Light  Through  Crystalline  Lens 393 

Superior  Fornix  and  Inferior  Fornix  of  Conjunctiva 304 

Crystalline  Lens 395 

A  Horizontal  Section  of  the  Eye-Ball 396 

The  Third  Cranial  or  Motor  ( )culi  Nerve 397 

The  Fourth  Cranial  or  Trochlear  Nerve 398 

Showing  Brandies  of  Fifth  Xerve 399 

Show  Distribution  of  Filth  Nerve  in  Reference  to  » >t  her  Structures. . .  400 

Cutaneous  Xerve  Supply  of  Head  and  Neck 401 

Meckel's  Ganglion  and  ( >tic  Ganglion |(i:; 

The  Sixth  Cranial  or  Abducens  Xerve 405 

Branches  of  Facial  Xerve 407 

Showing  Facial  Xerve  and  Superficial  Cervical  Plexus 109 

Origin  and  Distribution  of  Auditory  Xerve 411 

Showing  Distribution  of  Xinth,  Tenth,  Eleventh  Cranial  Nerves 413 

Showing  Pneumogastric  Xerve  and  Sympathetic  Ganglia 415 

Showing  Si  ructures  Passing  Through  the  Sphenoidal  Fissure 117 

Showing  the  Abdominal  Areas 419 

The  Permanent  Teeth 421 

A  Vertical  Section  of  Canine  Tooth 424 

The  Hard  Palate 426 

The  Bones  of  Orbit 128 

Showing  the  Sensory  Pathways  to  Brain 430 

Showing  the  Motor  Pathways  from  Brain 432 

The  Cavernous  Sinus  (Modified  from  Cunningham) 434 

Showing  Both  Sensory  and  Motor  Pathways 430 

The  Sutures  of  Skull 438 

Showing  Foramina  at  Base  of  Skull 440 

The  Inferior  Surface  of  Base  of  Skull 442 

Internal  Surface  of  Frontal  Bone 444 

External  Surface  of  Frontal  Bone 446 

Internal  Surface  of  Parietal  Bone 448 

External  Surface  of  Parietal  Bone 450 

External  Surface  of  Occipital  Bone 452 

Internal  Surface  of  <  >ccipital  Bone 15  1 

Posterior  View  of  the  Sphenoid  Bone 455 

Anterior  View  of  Sphenoid  Bone 450 

The  Pterygoid  Processes 457 

The  External  Surface  of  Temporal  Pone 1">S 

The  Petrous  Portion  of  the  Temporal  Hone 159 

400 

461 
162 

163 

10  1 

107 
170 
17:; 
176 

170 

182 

is.". 

188 
491 

10  1 


The  Temporal  Pone  Laid  ( >pen 

The  Inferior  Surface  of  Petrous  Portion  of  Temporal  Pone 

The  Nasal  Bone 

The  Lachrymal  Pone 

The  Internal  Surface  of  Superior  Maxillary  Hone   

External  Surface  of  Superior  Maxillary  Bone 

Internal  Surface  of  Malar  Bone 

External  Surface  of  Malar  Bone 

External  Surface  of  Inferior  Maxillary  Bone. 
Interna]  Surface  of  Inferior  Maxillary  Hone. 

Lateral  View  of  the  Ft  hmoid 

Superior  View  of  I  he  Ft  hmoid   

Inferior  Turbinated  Hone    

The  Vomer 

The  Palate  Bone  i  Posterior  Views)      


XIV 

Plate 

CCLXIII. 

(CI. XIV. 

CCLXV. 

CCLXVI. 

CCLXVII. 

(CI.  XVIII. 

(CI. XIX. 

(CI. XX. 

CCLXXI. 

CCLXXII. 

(CI. XXIII. 

CCLXXIV. 

(CI. XXV. 

CCLXXVI. 

(CI. XXVII. 

CCLXXVII1. 

(CI. XXIX. 

(CI. XXX. 

(CI. XXXI. 

(CI. XXXII. 

(CI. XXXIII. 

('('I. XXXIV. 

CCLXXXV. 

CCLXXXVI. 

(CI. XXX  VII. 

(CI. XXXVIII. 

CCLXXXIX. 

ccxc. 


LIST    OF   ILLUSTRATIOXS. 

Page 

The  Lateral  Mew  of  the  Palate  Bone 497 

The  Meatuses 500 

The  Uriniferous  Tubules 503 

Sagittal  Section  of  Kidney 506 

The  Female  External  Organs  of  Generation 509 

Colles'  Fascia  and  the  Triangular  Ligaments  of  Perineum 512 

The  White  Line  and  Ischio  Rectal  Fossa 515 

Showing  the  Muscles  of  Perineum 518 

The  Uterus,  Horizontal  Section 521 

A  Sagittal  Section  of  the  Female  ( >rgans  of  (  feneration 524 

The  Uterus  with  Vagina  Laid  Open 527 

A  Transverse  Section  of  Penis 530 

A  Horizontal  Section  of  Penis 533 

Testicle  and  Spermatic  Cord 53(i 

The  Testicle 539 

A  Sagittal  Section  of  the  Male  ( )rgans  of  Generation 542 

The  Mammary  Gland 545 

The  ( 'uter  Surface  of  the  Left  Pinna 548 

Diagrammatic  View  of  the  Organs  of  Hearing 551 

Posterior  View  of  the  Far  with  Auricular  Muscles 554 

The  Bony  Cochlea 557 

The  Bony  Cochlea  Cut  Through 560 

The  Interior  of  the  Labyrinth  with  Distribution  of  Auditory  Xerve.  .  .  563 

Interior  of  Bony  Labyrinth 566 

Malleus,  Incus  and  Stapes 569 

Forms  of  Congenital  Hernia? 572 

The  Lamphatic  Man 575 

A  Lymphatic  Xode 576 


Preface. 


Preface  to  Second  Edition. 

Six  years  ago  the  author  compiled  a  little  book  of  one  hundred  and  fifty 
pages  called  Anatomy  in  a  Nut  Shell,  which  was  the  outgrowth  of  his  studying 
and  teaching  anatomy  in  the  American  School  of  Osteopathy.  It  filled  its 
place  as  it  was  intended  only  as  an  aid  to  the  student  in  preparing  his  work. 
There  seemed  to  be  no  work  upon  anatomy  taken  up  in  a  teachable  and  sys- 
tematic manner  and  the  student  complained  that  it  took  more  time  to  find  his 
lesson  in  the  books  at  hand  than  to  learn  it  when  found. 

In  presenting  the  subject  of  anatomy  to  the  student,  we  first  teach  a  few 
rules  and  fundamental  principles  to  give  him  a  working  knowledge  of  the  sub- 
ject, and  then  we  take  up  the  work  complete  as  it  comes  in  the  human  body. 
For  instance  in  teaching  the  anatomy  of  the  arm  we  take  the  clavicle,  giving 
its  ossification,  articulations,  attachment  of  muscles  and  blood  supply.  Then 
the  origin  and  insertion  with  action,  blood  supply  and  nerve  supply  of  these 
muscles.     So  it  is  with  every  bone  of  the  upper  extremity  and  the  entire  body. 

What  is  gained  by  saying  that  the  greater  tuberosity  of  the  humerus  has 
three  muscles  attached  to  it,  namely  the  Supraspinatus,  Infraspinatus  and  Teres 
minor,  unless  we  learn  the  functions  of  these  muscles?  By  this  method  of  teach- 
ing anatomy  we  find  it  to  be  one  of  the  most  interesting  of  all  subjects  both  to 
teacher  and  pupil. 

The  original  book  of  one  hundred  and  fifty  pages  has  been  revised  ami 
enlarged  to  over  six  hundred  pages,  but  the  name  Anatomy  in  a  Nut  Shell  is 
retained,  because  any  book  of  six  hundred  pages  covering  such  an  inexhaustible 
subject  as  human  anatomy  would  be  a  Nut  Shell  indeed. 

In  preparing  this  work  the  following  authors,  through  their  writings,  have 
been  my  constant  companions:  Gray,  Gerrish,  Morris,  Denver.  Potter, Holden, 
Heath,  Cunningham,  McClellan,  Eckley,  Rockwell,  Butler,  Hale,  ami  last  but 
not  least,  Dr.  A.  T.  Still  has  been  my  inspiration  and  best  teacher. 

The  entire  work  is  given  in  lessons  so  that  each  day  the  student  has  some 
thing  definite  to  do. 

"He  who  every  morning  plans  the  transactions  of  the  day,  and  follows  out 
that  plan,  carries  on  a  thread  which  will  guide  him  through  the  Labyrinth  of 
the  most  busy  life." — Blair. 

"The  chief  art  of  learning  is  to  attempt     but   little   at   a   time."      Locke. 

What  was  omitted  in  the  first  edition,  such  as  the  origin  ami  insertion  of 
muscles,  is  here  given,  so  that  the  work  is  complete  in  itself.  Ami  any  one  who 
masters  this  work  can  justly  feel  proud  of  his  anatomical  knowledge. 

\v 


Xvi  PREFACE. 

The  author  was  most  fortunate  in  securing  Dr.  Win.  Most,  a  senior  student 
of  tin'  American  School  of  Osteopathy,  in  make  the  drawings,  and  he  is  espec- 
ially grateful  to  his  wife.  Dr.  Isabel  Cash  Laughlin  for  writingthe  entire  manu- 
scripl  the  lasl  time  over  and  assisting  in  proof-reading.  Dr.  A.  E.  Daugherty, 
editor  of  the  A.  S.  ().  Student,  deserves  special  mention  for  making  the  index. 

Preface  to  First  Edition. 

This  book  is  noi  intended  to  lake  the  place  of  any  standard  text-book  in 
anatomy,  hut  is  to  he  used  as  an  aid  for  the  student.  The  origin  and  insertion 
of  the  muscles  have  noi  been  given,  as  that  is  ou1  of  the  province  of  this  book. 
In  preparing  this  hook,  several  authorities  have  keen  consulted,  as  A.  T.  Still, 
Gray's  Anatomy,  Morris'  Anatomy,  Gerrish's  Anatomy,  Century  Dictionary, etc. 


ANATOMY  IN  A  NUTSHELL. 


LESSON  I. 


Anatomy  is  concerned  with  the  form,  structure  and  connections  of  the  parts 
of  the  body.     It  has  the  following  divisions: 

1.  Osteology  (os-te-ol-o-je)  is  the  anatomy  of  the  bones. 

2.  Syndesmology  (sin-dez-mol-o-je)  is  the  anatomy  of  the  joints. 

3.  Myology  (mi-ol-o-je)  is  the  anatomy  of  the  muscles. 

4.  Angiology  (an-je-ol-o-je)  is  the  anatomy  of  the  vessels. 

5.  Neurology  (nu-rol-o-je)  is  the  anatomy  of  the  nerves. 

6.  Splanchnology  (splangk-nol-o-je)  is  the  anatomy  of  the  viscera. 

7.  Adenology  (ad-en-ol-o-je)  is  the  anatomy  of  the  glands. 

8.  Dermatology  (der-mat-ol-o-je)  is  the  anatomy  of  the  skin. 

9.  Genesiology  (jen-e-ze-ol-o-je)  is  the  anatomy  of  the  generative  organs. 
Aponeurosis  (ap-on-u-ro-sis)  is  the  end  of  a  muscle  where  it  becomes  a 

tendon. 

(a)  It  is  any  fascia  or  fascial  structure,  especially  the  tendons  of  a  muscle 
when  broad,  thin,  flat  and  of  a  glistening  white  color. 

(b)  It  is  the  expansion  of  a  tendon  covering  more  or  less  of  a  muscle. 

(c)  It   is  a  thin,   whitish  ligament. 

The  name  was  given  to  these  structures  when  they  were  supposed  to  be 
expansions  of  nerves — any  hard,  whitish  tissue  being  then  considered  nervous. 
In  present  tisage  aponeurosis  is  nearly  synonymous  with  fascia,  but  it  is  oftener 
applied  to  the  fascia  like  tendons  of  muscles;  as  the  aponeurosis  of  the  external 
oblique  of  the  abdomen.     (Plate  XV.) 

Fascia  is  a  sheet  or  layer  of  dense  connective  tissue.  The  general  contour 
of  the  body  is  invested,  just  beneath  the  skin,  with  a  thin,  light  fascia,  as  dis- 
tinguished from  the  thicker,  tougher  and  more  densely  fibrous  deep  fascia 
which  invests  and  forms  sheaths  for  muscles  and  dips  down  among  the  mus- 
cles and  bundles  of  muscular  fibers  forming  intermuscular  septa. 

A  tendon  is  a  hand  or  layer  of  dense  fibrous  tissue  at  the  end  of  a  muscle 
for  attachment  to  a  hard  part.  A  very  hard  flat  tendon  is  called  fascia  and 
aponeurosis.  Tendons  are  directly  continuous  at  one  end  with  the  periosteum 
and  at  the  other  end  with  the'  fascial  tissue  which  invests  the  muscle. 

A  sinus  means  a  cavity  in  hone  or  other  tissue.  The  sinus  of  the  superior 
maxillary  hone  is  called  the  antrum  of  Highmore.  The  veins  of  the  dura  mater 
are  called  sinuses. 

17 


PLATE  I. 


'  THERE  ARE  200  BONES  IN  THE  BODY  EXCLUDING 
THE  BONES  OF  THE  MIDDLE  EAR -MALLEUS.  INCUS. 
STAPES,  ALSO  THE  SESAMOID  AND  THE  WORMIAN  BONES 


STAPES,  ALSO  THE  SESAMOID  AND  THE  WORMIAN  BONES.        V^_j   L  .     ^-^^fc 
THE  SESAMOID  BONES  ARE  FOUNO  IN  TENDONS  OF  ^^t^"^  fr 

MUSCLES.  THE  WORMIAN  BONES  ARE  IN  THE  SUTURES  :    J"   / 


OF  THE  SKULL. 


MANUBRIUM 
GLADIOLUS 
ENSIFORM  APPENDIX 


OLECRANON 


The  Bony   Max. 
18 


ANATOMY    IN    A    NUTSHELL.  19 

All  processes  of  bone  are  either  apophyses  or  epiphyses.  An  apophysis  is 
a  process  that  has  grown  from  the  bone  and  has  no  separate  ossific  center.  An 
epiphysis  has  a  separate  ossific  center  and  is  joined  to  another  bone  by  car- 
tilage. This  cartilage  becomes  ossified  but  this  change  does  not  make  the 
epiphysis  an  apophysis.  Once  an  epiphysis  always  an  epiphysis.  The  head 
of  the  femur  is  an  epiphysis  ami  the  neck  of  the  femur  is  an  apophysis. 

The  nutrient  arteries  of  the  bones  of  the  arm  and  forearm  run  towards 
the  elbow:  in  bones  of  the  lower  extremity  they  run  from  the  knee. 

Rule  1. — The  epiphysis  towards  which  the  nutrient  artery  runs  joins  the 
bone  first  always,  but  ossifies  last  in  all  bones  except  the  fibula. 

Rule  2. — When  there  is  but  one  epiphysis  then  the  nutrient  artery  runs 
towards  the  end  of  the  bone  which  has  no  epiphysis;  e.  g.,  the  clavicle  and  met- 
acarpals and  metatarsals.     (Plate  VII.) 

Rule  3. — When  there  are  two  or  more  nucleii  in  an  epiphysis  they  con- 
solidate before  the  epiphysis  joins  the  diaphysis. 

Rule  4. — The  epiphysis  which  ossifies  first  is  the  larger,  and  the  cartilage 
between  it  and  the  diaphysis  grows  longer  and  faster  than  the  cartilage  at  the 
other  extremity  of  the  bone. 

An  epiphysis  may  become  separated  from  the  diaphysis  and  such  an  in- 
jury may  be  mistaken  for  a  fracture  or  dislocation.  A  knowledge  of  this  prin- 
ciple is  of  great  importance  in  medical  jurisprudence;  e.  g..  the  epiphysis  at  the 
distal  end  of  the  femur  ossifies  at  the  ninth  month  of  fetal  life. 

The  covering  of  bone  is  called  periosteum.  It  covers  all  the  bone  except 
the  articular  cartilage  and  uives  attachment  to  tendons.  Periosteum  besides 
giving  attachment  to  the  tendons  of  muscles; 

1.  Gives  nutrition  to  the  bone. 

2.  Forms  all  capsular  ligaments. 

.'!.      Tends  to  hold  the  end  of  broken   bones. 

4.  From  it   the  bone  grows  in  thickness. 

5.  It  hinders  the  progress  of  contiguous  inflammation. 

A  long  bone  grows  in  length  by  the  development  of  the  epiphyseal  cartil- 
age and  interstitial  deposits;  in  thickness  from  the  osteogenetic  layer  of  the 
periosteum  and   interstitial  deposits. 

There  are  300  bones  in  the  body  (Platel.)  They  are  divided  into  long, 
short .  flat  and  irregular  ones.  90  of  the  bones  are  Long  ones  and  are  found 
in  the  extremities.  In  reality  a  long  bone  may  not  be  :is  long  as  a  Hat  or  irreg- 
ular one  o]-  even  a  short  bone.  e.  g.,  the  last  phlanx  is  shorter  than  the  os  calcis. 
The  long  bones  act  as  lexers  and  have  a  medullary  canal  in  the  center  of  each  ; 
and  a  shaft  called  diaphysis.  and  two  extremities.  They  are  developed  by 
osseous  deposits  in  cartilage.  In  each  upper  extremity  there  is  a  clavicle, 
humerus,  ulna,  radius,  five  metacarpal  and  fourteen  phalanges,  making  23  long 
bones  in  each  upper  extremity,  then  in  both  extremities  there  are  2x23  or  16 
long  bono.  In  each  lower  extremity  there  is  a  femur,  tibia,  fibula,  five  met- 
atarsals ami  fourteen  phalanges,  making  22  long  bones  in  each  lower  extremity, 
then  in  both  extremities  there  are  2x22,  or  II  long  bono.  The  46  long  bone- 
in  the  upper  extremity  and  the  44  long  ones  in  the  lower  extremities  make 


_>()  ANATOMY    IN    A    NUTSHELL. 

90  Long  bones.  There  are  30  short  bones.  They  also  are  developed  by  osseous 
it  in  cartilage  and  arc  found  in  the  extremities.  They  are  found  where 
strength  but  no1  much  motion  is  required.  In  each  carpus  (Plate  XXVI.)  there 
ones,  viz.,  scaphoid,  semi-lunar,  cuneiform,  pisiform,  trapezium,  trapezoid, 
08  magnum  and  unciform,  making  8  hones:  2x8  are  16,  the  number  of  short 
bonesinthe  two  upper  extremities.  In  each  ankle. (Plate  LIV.)there  are  7  bones, 
viz..  os  calcis,  astragalus,  navicular  or  scaphoid,  cuboid,  external  cuneiform, 
middle  cuneiform,  and  internal  cuneiform,  making  7  short  bones  in  each  tarsus; 
then  in  the  two  tarsi  there  are  2x7  or  14  short  bones;  the  14  short  bones  in 
the  lower  extremity  and  the  16  short  ones  in  the  upper  extremity  make  the 
30  short   bones. 

LESSON   II. 

There  are  40  flat  bones,  all  of  which  are  found  in  the  trunk,  and  head  ex- 
cept four  and  these  are  in  the  extremities.  They  are  the  two  patellae  and  two 
scapulae.  The  flat  bones  in  the  trunk  protect  the  viscera.  They  are  develop- 
ed by  osseous  deposits  in  membranes  and  consist  of  two  dense  layers  separated 
by  cellular  or  cancellated  osseous  tissue,  the  diploe.  There  are  the  two  parie- 
tal, frontal  and  occipital  in  the  cranium.  In  the  face  there  are  two  nasal,  two 
lachrymal  and  the  vomer.  In  the  thorax  24  ribs  and  the  sternum;  then  there 
ate  the  tun  innominata,  two  patellae,  two  scapulae,  making  40  Hat  bones  in  the 

body. 

There  are  io  Irregular  bones.  They  are  found  in  the  trunk  and  head. 
They  are  the  24  vertebrae,  the  sacrum,  coccyx,  two  temporal,  ethmoid. 
sphenoid    and  the  hones  of  the  face  except  the  two  nasal,    two  lachrymal  and 

the    Vomer.       Then    the    hvoid    holie. 

There  are  s  hones  in  the  cranium.  The  4  flat  ones  are  the  frontal,  two 
parietal  and  occipital:  the  4  irregular  ones  are  two  temporal,  sphenoid  and 
ethmoid. 

There  are  1  I  hones  in  the  face;  the  5  tlat  ones  are  the  two  nasal,  two  lachry- 
mal ami  vomer.  The  9  irregular  ones  are  the  two  superior  maxillary,  two 
malar,  two  palate,  two  inferior  turbinated  and    the  inferior  maxillary. 

Then  in  the  cranium  and  the  face  together  there  are  8  plus  14.  making  22 
hone.-.  In  the  trunk  there  are  75  hon<  s.  if  the  22  of  the  head  are  included.  In 
the  trunk  without  the  head  there  are  53  hones,  which  are  24  vertebrae,  24  ribs, 
sternum,  sacrum,  coccyx  and    1  wo  innominata.      In  the  extremities  there  are 

12  1  1 is,  64  in  the  upper  and  60  in  thelower.     In  the  pelvis  there  are  4  bones, 

two  innominata.  sacrum  and  coccyx.  \oi  counting  the  vertebra'  in  the  cranium 
there  an-  :::;  vertebra?;  7  cervical,  12  dorsal,  5  lumbar.  5  sacral  and  4  in  the 
coccyx.  There  are  12  pairs  of  iil>-.  7  of  which  are  true  and  5  false.  2  of  which 
are  float  Lng. 

Besides  the  200  hones  mentioned  there  are  sesamoid  bone-  which  are  de- 
veloped in  tendons  such  as  the  patellae,  but  these  on  account  of  their  size  ami 
shape  are  called  flat  ones;  and  the  wormian  bones,  which  are  found  in  the 
sutures  of  the  skull;  and  the  malleus,  incus  and  stapes  found  in  the  middle  ear. 


PLATE  II. 


The  Muscul  \i;  .Max. 
21 


WAToUY    IN     \     NUTSHELL. 

There  are  32  teeth:  in  each  jaw  there  is  one  pair  <>!'  canine,  two  pairs  of  incisors 
two  pairs  of  bicuspids,  ami  three  pairs  of  molars. 
The  eminences  of  bones  are: 

1.  Apophyses     an  example,  neck  of  the  femur. 

2.  Condyles,   which    mean    irregular  heads     example,  lower  part   of  the 
femur. 

:;.     Epiphyses     example,  head  of  femur. 

\.      Heads,  smooth  ami  convex,  found  in  joints  — mi  femur  and  humerus. 

0.  Spines,  sharp  and  slender     on   vertebrae. 

ti.     Trochanters,  for  turning  joints     on  the  femur. 

7.  Tubercles,  -mall  tuberosities     deltoid  tubercle  on  clavicle. 

8,  Tuberosities,  broad  prominences— on  the  humerus. 
Besides  these  s.  there  are  11  other  prominences  on  hones. 

1.  Azygos,  without  a  fellow— odontoid  on  axis. 
•_'.     Clinoid,  like  a  bed     on  the  sphenoid  hone. 

:;.  Coracoid,  like  a  crow's  beak-  on  the  scapula. 

-1.  Coronoid,  like  a  crown     on  the  ulna. 

5.  llaninlar,    hook-like      on    sphenoid. 

ii.  Malleolar,   mallet-like     lower  part   of  fibula. 

7.  Mastoid,  nipple-like     on   temporal   hone. 

8.  Odontoid,  tooth-lik< — on  axis. 

9.  Pterygoid,  wing-like     on  sphenoid. 

10.  1 1 c » —  t  mm,  a  beak      on  sphenoid. 

11.  Spinous,    thorn-like     on    sphenoid. 

12.  Squamous,  scaly     on  temporal. 
]'.'>.  Styloid,  pen-like — on  temporal. 

14     Vaginal,  ensheathing     on  temporal. 
There  arc  •">  articular  cavities  in  bones. 
1.     Alveolar,  socket-like-    tooth  in  the  jaw. 
'_'.     Cotyloid,  cup-lik( — hip-joint. 
:;.     I'acet .  face     on  the  »reat  tuberosity. 
I.     Glenoid,  shallow-  shoulder-joint. 
5.     Trochlear,  pulley-like     in  the  orbit. 
There  arc   10  mm  -articular  cavities. 

1.  Aqueducts     Aqueduct  of  Fallopii  in  temporal  hone. 

2.  Canal-      Vidian  canal  in  sphenoid  hone. 

:'..  (ell-     Mastoid  cells  in  mastoid  process  of  temporal  bone. 

1.  Depressions     Meckel's  cave  on  petrous  portion  of  temporal  bone. 

5.  Fissures      Sphenoidal  fissure  in  sphenoid  hone. 

•  '>.  Foramina     Base  of  skull. 

7.  Fossae;  also  at  base  of  skull. 

v      Grooves     On    inner    surface  of   Parietal    bone  for  middle  meningeal 
artery. 

!•.      Notches      Ethmoid    notch    on    frontal    hone. 

10.     Sinusi  -     Frontal  -inn-,  superior  maxillary  sinus  which  is  called  Antrum 
of  Highmore. 


ANATOMY    IX    A    NUTSHELL. 


23 


1.  Radius  means  spoke  27. 

2.  Carpus — wrist  28. 

3.  Scaphoid— boat  29. 

4.  Semilunar — half  moon  30. 
.").  Cuneiform — wedge-like  31. 

6.  Pisiform — pea-like  32. 

7.  Trapezium — table  33. 

5.  Trapezoid — table  shape  o4. 
9.  Os  Magnum — large  bone   .  35. 

10.  Unciform — hook  36. 

11.  Metacarpus — beyond  the  wrist      37. 

12.  Phalanges — fingers  and  toes  3S. 

13.  Pelvis— basin  39. 

14.  Femur — thigh  40. 

15.  Patella — small  pan  41. 

16.  Tibia— flute  42. 

17.  Fibula — clasp.  43. 

18.  Obturator — closed .  44. 

19.  Glenoid — shallow  45. 

20.  Cotyloid— cup-like  46. 

21.  Tarus— ankle  47. 

22.  Os  calcis— heel  48. 

23.  Astragalus— die  49. 

24.  Navicular  or  scaphoid — boat         50. 
26.  Cuneiform — wedge-like  51. 

25.  Thyroid— shield.  52. 


Cuboid — cube 

Cranium — helmel 

Frontal—  forehead 

Occipital — against  the  head 

Parietal — wall 

Ethmoid — sieve 

Sphenoid — wedge 

Temporal — time 

Nasal — nose 

Superior  Maxillary — jaw  bone 

Inferior  Maxillary — mandible  . 

Lachrymal — tear 

Malar — cheek 

Palate — palate 

Turbinated — whirl 

Vomer — ploughshare 

Vertebra — to  turn 

Thorax — chest 

Sacrum — sacred 

( loccyx — cuckoo 

Innominata — without  a  name 

Clavicle — key 

Scapula — spade 

Humerus — arm 

Ulna — elbow 

Sternum — breast  plate 


LESSON  III. 

Muscles. — We  have  said  there  are  200  bones  in  the  body,  but  the  num- 
ber of  muscles  cannot  be  given  exactly,  for  there  are  some  which  at  times  are 
absent  and  again  double.  There  are,  ordinarily,  thirteen  muscles  from  the  knee 
to  the  ankle,  but  there  may  be  only  twelve  or  there  may  be  fourteen,  as  the 
Plantaris  may  be  absent  or  double. 

The  [nfracostals  vary  in  number,  however,  there  are  generally  ten  pairs. 
Ordinarily  there  are  twenty  muscles  in  the  forearm,  sometimes  nineteen,  other 
times  twenty-one  as  the  Palmaris  longus  may  be  absent  or  double.  So  it  is  im- 
possible to  give  the  exact  number.  However,  there  are  more  than  550  muscles 
in  the  human  body.  (  Plate  II.)  The  muscles  give  form  to  the  body  and  move 
it  from  place  to  place.     They  take  their  names  in  various  ways. 

1.  From  the  attachment,  as  Sterno-cleido  mastoid,  which  mean-  this 
muscle  is  attached  to  the  sternum,  and  the  clavicle  (key)  and  the  mastoid  pro- 
cess of  the  temporal   bone. 


24 


ANATnMV    IN    A    NUTSHELL. 


2.  From  the  number  of  parts,  as  Biceps,  which  means  Two  heads,  and 
Triceps,  which  means  three  head-. 

From  the  shape,  as  Deltoid,  like  the  Greek  letter  delta,  inverted. 

1  From  the  function,  as  Levator  anguli  scapulae,  which  means  to  lift 
the  angle  of  the  scapula. 

From  the  position,  as  Subclavius  and  Subscapularis  which  means  under 
the  clavicle  and  under  the  scapula. 

6.  From  the  function,  attachment  and  shape,  as  Pronator  radii  teres, 
which  means  this  muscle  first  pronates,  second  it  is  attached  to  the  radius,  and 
third  it   is  round     teres  I. 

.Muscle*,  have  tv\<>  or  more  points  of  attachments;  the  part  which  is  most 
stationary  is  called  the  "origin"  and  is  generally  the  larger;  the  most  movable 

PLATE  III. 


Showing  the  Origin  and  Ensertion  op  the  Biceps. 


part  is  called  the  "insertion"  and  is  generally  the  smaller  pan  of  the  attach- 
ment of  the  muscle.  (Plate  ill.)  Muscle-  must  have  a  blood  and  nerve 
supply  in  order  to  be  in  a  healthly  condition.  Principle:  Function  makes  struc- 
ture  and  the  cessation  of  function  leads  to  the  disappearance  of  structure.  For 
instance,  in  the  primative  man  the  Pectorialis  minormuscle  was  continued  from 
the  coraciod  process  of  the  scapula  to  the  humerus;  now  this  part  of  the  muscle 
is  a  Ligament.  Again,  the  internal  lateral  ligament  of  the  knee  was  at  one  time 
a  part  of  the  Adductor  magnus  muscle.  Thelong  external  lateral  Ligament  of 
the  knee  was  at  one  time  a  pari  of  the  Peroneus  Longus,  and  the  ligamentum 
teres  belonged  to  the  Pectineus  muscle. 

Joints  \m>  Ligaments.  A  joint  is  made  up  of  two  or  more  hones,  a  syn- 
ovial membrane,  articular  cartilage,  white  fibrous  cartilage,  and  ligaments, 
and  is  for  the  purpose  of  motion.     The  bones  are  larger  where  they   enter  into 


A.NATOMY    IN    A    NUTSHELL. 


25 


the  joint  and  are  covered  with  articular  cartilage.  This  cartilage  has  no  blood 
vessels,  is  a  hylaine  variety,  and  is  nourished  by  the  lymph.  These  bones  are 
held  together  by  ligaments  (to  bind)  which  are  flexible  but  not  extensible. 
Joints,  like  muscles  must  have  blood  and  nerve  supply. 

Hilton's  Law — A  nerve  trunk  which  snpplies  a  joint  supplies  the  muscle 
which  moves  the  joint  and  the  integument  over  the  fullest  insertion  of  the  mus- 
cle .     The  Circumflex  nerve  to  the  shoulder  joint  is  a  good  example  of  this  law. 

There  are  three  great  classes  of  joints  in  the  body: 

A.  Immovable  or  Synarthrosis. 

B.  Partly  movable  or  Amphiarthrosis. 
('.  Freely  movable  or  Diarthrosis. 

PLATE  IV. 


ANT.  PRIMARY  BRANCH 


SPINAL    NtHvb 


POSTERIOR  PRIMARY  BRANCH 


ANT    OR  VENTRAL  R00T-M0TUR 


EXT.  DIVISION 


INT  DIVISION 


1  -  GALL  6  -  VENTRO  LATERAL  ASSOCIATION 

2  -  BURDACK  7  -  DEEP  LATERAL  ASSOCIATION 

3  -  MARGINAL  9  -  DIRECT  PYRAMIDAL 

4  -  DIRECT  CEREBELLAR        9  -  CROSSED  PYRA  MIOAL 

5  -ASCENDING  LATERAL  TRACT  (GOWERSt    10  COMMA 

A  Transverse  Section  of  the  Spinal  Cord. 


Under  (A)  Synarthrosis  we  have  the  following: 

1.  True  sutures  or  sutura  vera. 

a.  Dentata  ;is  interparietal. 

b.  Serrata  as  interfrontal. 

c.  Limbosa  as  fronto-parietal. 

2.  Sutura  notha. 

a.  Squamosa  as  squamo-parietal. 

b.  Harmonia  as  intermaxillary. 

3.  Schindylesis  as  the  sphenoid  with  the  vomer. 

4.  Gomphosis,   as   the   teeth. 

5.  Synchondrosis,  which   means  the  union  of  bones  by  mean-  of  fibrous 
or  elastic  cartilage,  e.  g.;  epiphyseal  line.-. 


WATiiMV    IN    A     NUTSHELL. 

I'..  Amphiarthrosis. 

I.  Symphysis,  as  between  bodies  of  vertebrae ;  and  the  anterior  part  of 
the  innominata  :  symphysis  pubes.  This  kind  of  joint  has  no  synovial  membrane. 
•_'.  Syndesmosis,  as  the  inferior  tibio-fibular  articulation. 
c.   Dlarthrosis.     All  the  diarthrosis  or  movable  joints  are  represented  in 
the  shoulder  girdle  and  the  upper  extremity. 

1.  A.rthrodia  (gliding)  in  the  acromio-clavicular-joint. 

2.  Enarthrodia,  (ball-and-socket)  in  the  shoulder-joint. 
:;.     ( iinglymus  (hinge)  in  the  elbow. 

\.  Trochoides  or  Pivet-joint,  in  the  superior  radio-ulnar  joint. 

5.  Condyloid,  as  the  wrist-joint,  having  all  movements  except  axial 
rotation. 

6.  Reciprocal  Reception  (saddle  shaped-joint)  in  the  carpo-metacarpal 
joint  of  the  thumb. 

Ligaments  take  their  names  from  the  bones  they  join,  as  sterno-clavicu- 
lar  ligamenl  which  joins  the  sternum  and  the  clavicle.  When  it  goes  across 
a  notch  or  groove  it  is  called  a  transverse  ligament  and  when  it  goes  around  a 
joint  it  is  culled  a  capsular  ligament.  Ligaments  are  composed  mostly  of  white 
fibrous  tissue;  the  ligaments  subflava,and  the  ligamentum  nucha'  of  the  lower 
animals  arc  yellow  elastic  tissue. 

Nerves.  If  a  nerve  goes  to  integument  it  is  called  ■•cutaneous;"'  if  it  goes 
to  muscles,  i1  is  called  "muscular;"  if  it  goes  to  muscles  and  integument,  it  is 
called  "  musculocutaneous. n  There  are  twelve  pairs  of  cranial  nerves  and 
thirty-one  pair-  of  spinal  nerves.  All  spinal  nerves  are  compound  nerves  be- 
came they  have  an  anterior  root  which  is  motor  and  a  posterior  root  which  is 
sensory.  These  two  roots  unite  to  form  the  nerve  which  contain-  both  motor 
and  sensory  fibers.  Bach  nerve  as  it  leaves  the  spinal  foramen  divides  into  an 
anterior  and  posterior  branch. 

Principle  l.  (Plate  IV.)  Posterior  nerve  roots  are  larger  than  anterior 
nerve  roots,  with  the  single  exception  of  the  first  cervical.  They  are  from  one 
and  one-half  to  three  times  as  large. 

Principle  II.  The  anterior  branches  are  larger  than  the  posterior  branches 
in  all  cases  except  the  firsl  and  second  cervical  nerves. 

Principle  III.  The  posterior  branches  divide  into  an  internal  and  external 
division  in  all  cases  except  the  firsl  cervical,  fourth  and  fifth  sacral,  and  coc- 

■  !  nerve-. 

Principle  IV.     The  anterior  branches  make  the  plexuses. 

Principle  V.  (Plate  V)  The  posterior  nerve  root  has  a  ganglion  upon  it 
which  lies  in  the  intervertebral  foramen,  outside  the  sac  of  the  dura  mater,  ex- 
cept the  first  one  which  is  not  always  present,  and  when  present  is  situated 
within  the  dura  mater.  This  one.  and  the  second,  are  placed  on  the  arches  of 
the  vertebra  over  which  the  nerves  pass.  The  ganglia  of  the  last  four  sacral 
nerves  are  situated  outside  the  dura  mater  bu1  in  the  spinal  canal;  the  coccy- 
geal ganglion  when  presenl  is  within  the  dura  muter.  The  nervi  nervorum  are 
nerve  filament^  going  to  the  nerves  and  the  nerve  sheaths. 


ANATOMY    IN    A    NUTSHELL. 


27 


LESSON   [V. 

The  roots  of  the  first  and  second  spinal  nerves  pass  outward  at  right  angles- 
All  the  rest  pass  obliquely  downward  and  outward,  and  as  the  cord  ends  at  the 
second  lumbar,  the  lower  roots  have  a  long  course  before  they  leave  the  canal, 
and  are  situated  around  the  filnni  terminale  of  the  spinal  cord  forming  the 
cauda  equina. 

A  motor  nerve  is  any  nerve  whose  function  is  to  excite  muscular  conn-ac- 
tion, anil  thus  effect  movement  in  an  animal  body.  Most  nerves  are  mixed  in 
character  or  sensorimotor,  effecting  both  motion  and  sensation. 

A  sensory  nerve  is  a  nerve  conveying  sensory  impulses,  or  more  strictly, 
one  composed  exclusively  of  sensory  fibers;  nearly  equivalent  to  afferent  nerve. 

Vasomotor  nerves  are  those  which  supply  the  muscular  coats  of  the  blood- 
vessels. 

A  nerve  center  is  a  group  of  ganglion-cells  closely  connected  with  one  an- 
other and  acting  together  in  the  performance  of  some  function,  as  the  cerebral 
centers, 

Of  the  cranial  nerves,  some  are  compound,  some  are  motor  and  others  are 
nerves  of  special  sense.  They  take  their  names,  olfactory,  optic,  etc.,  from 
their  function,  but  the  names,  first,  second,  etc.,  from  the  order  of  piercing  the 
dura  mater  from  before   backward. 


TABLE  OF  CRANIAL  NERVES. 


Name. 


Distribution. 


Fitncton. 


Mktiiod  of  Ex  it 


1st.  Olfactory. 

Upper  third    of  nasal  cavity. 

Special  sense 
Smell. 

Cribiform   Plate   of  Eth- 
moid. 

2nd.  Optic. 

Retina. 

Special  sense 
Sight. 

Optic  Foramen. 

.lid,  oculo- 
motor. 

Muscles  of  eyeball  except    In- 
ternal   rectus   and     Superior 
oblique. 

Motor. 

Sphenoidal  fissure. 

4th.  Trochlear. 

Superior  oblique  of  eyeball. 

Motor. 

( Ordinary  Sense 

and  motor. 

sphenoidal  Fissure. 

5th.  Trificial. 

Sensory  part  to    lace,  fore   part 
of  scalp,   external    car.  eye, 
teeth, gum,  cheek,    lore   part 
of  tongue. 

Motor  part  to  muscles  of  nias- 

cation. 

<  tphthalmic   division  thro 
Sphenoidal  Fissure. 
Superior  Maxillary  thro 
Rotundum,     [n  f  eri  <>  r 

Maxillary  thro  Ovale. 

6th.  Abducent. 

Externa]  rectus  muscle   of  eve 

ball. 

Motor. 

Sphenoidal    fissure. 

28 


ANAIOMV    IX    A    NUTSHELL. 

TABLE  OF  CRAN1  M-  NERVES— Continued 


Name. 


7th.    Facial. 


8th.    Auditorx  . 


9th.   Ulosso- 
Pharyngeal 


I  >l-l  KIBUTION. 


Function. 


Method  of  Exit. 


Superficial  muscles   <>f  lace, 

Frontalis,  Platysma,    Stylo- 

boid    and  posterior  belly  or  Motor, 
Digastric. 


Internal  Auditory  Meatus 
a  n  (1  leaves  l>y  Stylo- 
mastoid Foramen. 


Special   sense, 
Membranous  labyrinth  oi  ear.      (hearing)  and 

Equilibrium. 


Internal  Auditory  Meatus; 
remains  in  ear. 


Pharynx  and  hind  partof  ton 
gue;  some  motor  fibers. 


Special  sense      jugular  Foramen. 

(taste).  Ord'y 

Sense,  Motor. 


S<  M-' 'iy  in  external  ear,  motor 


loth-    Pneumo-  and    8ensory    to     pharynx  . 

,,.,s.iri,.  or  \'-i  ii  <>rdinar\    sense 

_asun  oi    \  a-  larynx,  trachea,  lungs,  oeso-  •   ,  Jugular  Foramen, 

mis  ,  '  ,i.i       and  motor. 

-"  •  phagus,  stomach,  heart,  and 


pm 

sometimes  to  li\  er 


l  l  tli.  Spinal 

Accessory.  Motor  to  Trapezius  and  Sterno- 

mastoid  muscles.    Rest  is  ac-  Motor, 
cessory  t<>  the  pneumogastric. 


.1  ugular  Foramen. 


lJth.    Hypo- 
glossal 


Muscles  of  tongue. 


Motor. 


Anterior  Condyloid  Fora- 
men. 


LESSON   V. 

ART  I.  K  II.-. 

The  arterial  system  consists  of  two  separate  divisions  of  circulations.  The 
pulmonary  arterywith  its  branches  forms  the  lesser  or  pulmonary  circulation, 
and  the  aorta  with  its  branches  forms  the  greater  or  systemic  circulation. 

Blood  vessels.  Vasa  vasorum  are  blood  vessels  which  supply  the  larger 
arteries.  The  blood  circulates  through  the  body  to  nourish  the  various  parts. 
The  circulation  of  the  blood  was  demonstrated  by  Harvey  in  1628.     All  ves 

sels  which  carry  1>I 1  from  the  heart  are  arteries,  and  those  which  carry  blood 

to  the  heaii  are  veins.  The  connecting  link  between  the  arteries  and  the  veins 
is  the  capillaries.  Harvey  was  not  able  to  sec  these  connecting  links  for  they 
are  microscopic  and  the  microscope  was  no1  invented  until  some  years  later. 

Harvey  said  the  l>l I  filtered  through  the  tissues  from  the  arteries  to  the  veins, 

which  is  not  very  far  wrong.  Malpighi  discovered  the  capillaries  in  1661. 
As  a  rule  the  arteries  carry  pure  or  oxygenized  blood,  and  the  veins  carry 
impure  or  non-oxygenized  blood,  but  there  are  exceptions  to  this  rule  forthe 
pulmonary  artery  carries  impure  blood  and  the  pulmonary  veins  carry  pure 
blood.  Perhaps  the  puresl  Mood  in  the  body  is  in  the  right  renal  vein. 
When  the  blood  enters  the  kidney  it  is  as  pure  as  when  it  left  the  left  ventricle 
of  the  heart  and  in  the  kidney  it  throws  off  more  impurities  than  it  takes 
from  the  kidney.  The  left  renal  vein  receives  the  spermatic  vein  in  the  male 
and  the  ovarian  vein    in  the  female,    SO  it  contains    blood  less    pure    than    the 


PLATE  V 


GLOSSOPHARYNGEAL 
PNEUMOGASTRIC 
SPINAL  ACCESSOR 
CERVICAL 


— ~_~" — CKvV     <  V-  in 

— 1st  _j~V  ' 


SUPERIOR  CEREBELLAR  PEDUNCLt 

IDDLE  CEREBELLAR  PEDUNCLE 

NFERIOR  CEREBELLAR  PCQUNCLE 


TERMINAL  CONE 


VENTRAL  ROOTS 


FILUH     TERMINAll 


Posterior  View  of  the  Spin  w.  <  '< 

29 


30  \N  V.TOM1     1\    A    NUTSHELL. 

righl  renal  vein.  These  veins  of  the  righl  side  enter  into  the  inferior  vena 
cava  :iinl  have  valves. 

The  heart  is  a  voluntary  muscle  (straited)  in  structure  bill  is  presided  over 
by  the  sympathetic  nerve  which  makes  it  involuntary  in  action.  The  average 
weighl  of  the  heart  is  about  11  ounces.  Its  covering  is  called  pericardium, its 
lining  endocardium,  and  the  muscle  itself  is  called  myocardium.  It  has  four 
chambers,  the  two  upper  ones  arc  the  auricles  (ears)  and  the  two  lowerones 
ventricles  (bellies).  The  two  auricles  contract  at  the  same  time  that  the  ven- 
tricle- expand,  and  vice  versa.  The  contraction  is  called  the  systole  and  the 
expansion  the  diastole.     The  systole  is  the  work,  and  the   diastole  is  the  rest. 

Capillaries  arc  not  found  in  cartilage-  epithelium — epidermis.  The  net 
work  of  capillaries  is  very  close  in  the  lungs  mucous  membrane — muscle  and 
adipose  tissue  and  in  the  gray  matter  of  the  brain  and  cord.  The  capillary 
meshes  an'  wider  and  the  vessels  fewer  in  the  fascia — aponeurose — tendons 
and  ligaments.  In  their  simplest  form  the  capillaries  consisl  only  of  endo- 
thelial lining  of  the  arteries  and  veins  with  which  they  are  connected,  being 
both  elastic  ami  contractile,  their  lumen  varies  under  pressure.  They  are 
microscopic  and  in  order  to  get  a  drop  of  blood  many  musl  be  ruptured.  Arter- 
ies and  veins  have  nerves  called  vaso-motor  which  forms  a  net-work  around 
the  muscular  coat,  especially  of  the  arteries. 

\  EINS. 

Veins  are  found  in  almosl  all  the  tissues  and  carry  the  blood  from  the  cap- 
illaries to  the  heart.  A.s  they  are  generally  larger  and  more  numerous  than 
the  arteries,  their  total  capacity  greatly  exceed-  that  of  the  arterial  system. 
Not  only  the  smaller  branches,  but  even  the  larger  trunks  communicate  with 
each  other  very  freely.  The  venous  system  has  two  distind  subdivisions,  the 
pulmonary  ami  the  systemic. 

The  pulmonarj  veins  aid  in  the  pulmonary  circulation  and  convey  arterial 

bl 1  to  the  left  auricle;  they  are  but  slightly  larger  than  their  arteries, and  have 

no  valvt  s. 

The  systemic  veins  aid  in  the  general  circulation  and  convey  venous  blood 
to  the  righl  auricle.  They  are  divided  (systemically)  into  three  sets;  super- 
ficial, deep,  and  sinuses.  The  superficial  or  cutaneous  veins  lie  just  under  the 
skin  between  the  layers  of  the  superficial  fascia;  they  pierce  the  deep  fascia  to 
empty  into  the  deep  veins.  The  deep  veins  usually  accompany  the  arteries 
and  are  enclosed  in  the  same  -heath.  There  i-  generally  only  one  vein  with 
each  of  the  larger  arteries  as  the  subclavian  but  two  (venae  comites)  ac- 
company each  of  the  -mailer  arteries  as  the  radial,  and  all  the  arteries  of  the 
lower  extremities  excepl  the  femoral  artery, one  lying  on  each  side  of  them ;  in 
certain  regions  they  do  nol  accompanythe  arteries.  The  sinuses  are  venous 
channels  which  are  found  only  in  the  skull  ami  are  formed  by  a  separation  of 
the  layer-  of  the  dura  mater:  they  are  lined  by  endothelium. 

The  arteries  and  veins  have  threecoats;  fir-t  the  tunica  intima,  second  the 
tunica  media  and  third  the  tunica  externa  (adventitia).  This  third  coat  is  the 
"tily  one  not  ruptured  in  ligation  of  an  arterv.     The  tunica  media  has  muscular 


PLATE  VI. 


The  Brachial  Plexi  s. 
31 


32  ANATOMY    IN    A    NUTSHELL. 

fillers  in  it  and  supplied  with  vasomotor  nerve-  (vaso-constrictor  and  vaso- 
dilator). These  nerves  run  in  the  same  -heath  and  are  part  of  the  sympathet- 
ic nervous  system.  The  vaso-constrictor  acts  to  a  greater  or  lesser  degree  at 
all  times;  the  vaso-dilator  acts  upon  the  constrictor  and  inhibits  its  action. 

The  artery  which  passes  over  a  joint  gives  off  branches  above  and  below 
the  joint  and  these  branches  run  towards  the  joint  and  join  one  another.  This 
joining  is  called  anatsomosis.  Its  purpose  is  for  the  blood  to  run  in  these  small 
arteries  as  a  mean-  of  passing  the  joint  when  the  main  one  is  closed.  This  cir- 
culation i-  called  collateral.  Arteries  and  veins  hear  a  certain  relation  to  one 
another. 

Rule.— (Plate  VIII.)  Above  the  diaphragm  veins  are  are  on  the  same 
level,  or  in  front  of  their  companion  arteries.  Below  the  diaphragm  the  arter- 
ies are  on  the  same  level,  or  in  front  of  their  companion  veins,  excepting  the 
renal  and  the  profunda. 

The  tYtiis  gets  it-  food  and  oxygen  from  the  placenta,  while  after  birth  the 
food  come-  through  the  alimentary  canal  and  the  oxygen  through  the  lungs. 
In  tracing  the  circulation  after  birth  we  start  with  the  blood  in  the  right  auricle: 
a  systole  of  the  heart  -ends  it  through  the  tricuspid  valve  into  the  right  ven- 
tricle; here  a  systole  sends  it  through  the  semilunar  valves  into  the  pulmonary 
artery  ami  the  lungs,  where  it  gives  n{]  carbon  dioxid  and  receives  oxygen;  it 
i<  continued  from  the  lungs  through  the  pulmonary  veins  (three  to  five)  to  the 
left  auricle  of  the  heart,  then  a  systole  sends  it  through  the  bicuspid  valve  into 
the  left  ventricle;  from  here  a  systole  sends  it  through  the  aorta  to  all  parts  of 
the  body,  to  pas-  through  the  capillaries  and  to  be  collected  into  the  superior 
and  inferior  vena-  cava-  which  empty  into  the  right  auricle  of  the  heart. 

Veins  have  valves  which  keep  the  blood  from  running  back  in  its  course. 
All  veins  do  not  have  valves;  some  of  those  which  do  not  have  valves  are  the 
veins  of  the  dura  mater,  or  sinuses,  the  pulmonary  veins,  veins  of  the  portal 
system  and  those  of  the  spinal  cord.  The  others  will  be  mentioned  when 
described. 

Arteries  a-  a  rule  do  not  have  valves,  but  there  is  an  exception  to  this  also; 
the  pulmonary  artery  has  valves.  Veins  receive  tributaries,  or  radicles;  arter- 
ies break  into  branches.  The  portal  vein  breaks  into  branches  like  an  artery 
and  the  vertebral  arteries  join  like  a  vein  to  make  the  basilar  artery.  The 
veins  are  in    two  -el-;  the  superficial   and   the  deep;  the  superficial  ones  are   in 

the  superficial  fascia,  but  send  communicating  branches  to  the  deep  veins. 
The  deep  veins  accompany  the  arteries  in  the  extremities  and  there  are  two  for 

each  artery:  they  are  called  vena'  comites.  They  are  presenl  in  the  arm  and 
forearm  and  from  the  knee  to  the  ankle,  but  not  from  the  hip  to  the  knee.  The 
veins  are  larger  than  the  arteries.  If  they  were  all  put  into  one  vessel  it  would 
be  the  shape  of  ;1  cone  with  the  apex  at  the  heart  ami  its  base  at  the  surface  of 
tli.'  body  because  the  combined  area  of  the  tributaries  is  greater  than  that  of 
the   main  veins. 


AXATOMY    IN    A    NUTSHELL. 


33 


LESSON   VI. 

In  the  fetal  heart  the  Eusatchian  valve  is   large.       The   foramen    ovale 

which  joins  the  two  auricles  gives  a  free  communication  between  them  until 
the  middle  of  fetal  life,  at  which  time  a  valve  grows  from  the  posterior  wall  of 
the  right  auricle  to  the  left  of  the  foramen  ovale,  and  prevents  the  blood  from 
passing  through  except  from  right  to  left.  In  twenty  per  cenl  of  the  cases  the 
foramen  ovale  remains  open  throughout  life.      (Plate   IX.) 

PLATE  VII. 

PHALANGES.  TWO 
CENTERS  FOR  EACH  BONE.  ONE  FOR  SHAFT.  ONE  FOR  (£ 
METACARPAL  EXTREMITY. 


APPEAR  BETWEEN  THE 
THIRD  AND  FIFTH  YEAR 
CONSOLIDATE  IN  THE 
EIGHTEENTH  YEAR. 


APPEAR  IN  THE  THIRD 

CONSOLIDATE  IN  THE 
TWENTIETH  YEAR 


METACARPUS 
TWO  CENTERS  FOR  EACH  BC 
ONE  FOR  SHAFT.  ONE  FOR 
DIGITAL  EXTREMITY  EXCEPT  FIRST 


CARPUS. 
ONE  CENTER  FOR  EACH  BONE 
ALL  CARTILAGINOUS  AT  BIRTH 


APPEARS  IN  THE  THIRD  YEAR. 

CONSOLIDATES  IN  THE  ' 

TWENTIETH  YEAR. 


Nutrient  Arteries  of  Hoxk.s  ok  1Iwi>. 


The  ductus  arteriosus     which   is  aboul     half  an  inch     long  joins  the    de- 
scending aorta  just  below  the  origin  of  the  lefl  subclavian  artery. 

It  arises  from  the  left    pulmonary  artery     at  first  from  the  common  pul- 
monary. 

The  hypogastric    or  umbilical  arteries  arise  from   the  internal  iliac,  and 
after  passing  beside   the   bladder     go    through    the   umbilicus     to    the   placenta 
a 


34  ANATOMY    IN    A    NUTSHELL. 

The  umbilical  win  passes  from  the  placenta  to  the  under  surface  of  the 
liver  going  through  the  umbilicus  and  the  free  margin  of  the  suspensory  liga- 
ment. At  the  transverse  fissure  this  vein  divides  into  two  branches.  A  large 
<»ne  which  is  joined  by  the  portal  vein  and  enters  the  right  lobe  of  the  liver. 
A  smaller  one  the  ductus  venosus — joins  the  left  hepatic  vein  at  its  junction 
with  the  interim'  vena  cava.  Before  it  divides  the  umbilical  vein  gives  branches 
to  the  left,  quadrate,  and  Spigelian  lobes. 

The  pure  blood  coming  from  the  placenta  in  the  umbilical  vein  reaches  the 
interim-  vena  cava  in   three  ways; 

1.  A  small  quantity  via  ductus  venosus  into  the  hepatic  veins  and  in- 
ferior vena  cava. 

2.  Smne  enters  the  liver  directly  and  then  passes  through  the  hepatic  veins. 
:!.   Most  of  it  passes  through  the  liver  with  the  portal  venous  blood  and 

then  through  the  hepatic  veins. 

In  the  inferior  vena  cava  all  this  blood  mixes  with  venous  blood  from  the 
lower  extremities  and  abdominal  wall.  It  now  enters  the  right  auricle  from 
which  it  passes  to  the  lefl  auricle  through  the  foramen  ovale  being  guided  by 
the  Eustachian  valve.  In  the  lefl  auricle  it  mixes  with  the  blood  which  comes 
from  the  pulmonary  veins,  which  is  venous  and  a  small  amount.  It  now  passes 
through  the  auriculo-ventricular  opening  into  the  left  ventricle,  from  here 
through  the  aorta  to  the  head  and  upper  extremity,  some  passing  into  the  de- 
scending aorta.  The  venous  blood  from  the  upper  extremities  and  head  de- 
scends in  the  superior  vena  cava  into  the  right  auricle  of  the  heart  and  here  it 
mixes  with  a  small  pari  of  the  blood  from  the  inferior  vena  cava.  From  here  it 
passes  through  the  auriculo-ventricular  opening  to  the  right  ventricle.  A 
systole  sends  the  blood  from  the  right  ventricle  into  the  pulmonary  artery,  a 
small  pari  of  the  blood  passing  into  the  lungs  and  the  remainder  goes  through 
the  ductus  arteriosus  to  the  descending  aorta,  where  it  mixes  with  blood  from 
the  left   ventricle  after  it   has  passed  through  the  arch  of  the  aorta.     Most  of 

the  lil 1  in  the  descending  aoria  passes  through  the  umbilicus  to  the  placenta, 

and  the  rest  to  the  lower  limbs  and  viscera. 

The  adult  gets  nourishment  from  the  alimentary  canal  and  oxygen  from  the 
lungs.  The  placenta  acts  both  as  a  nutritive  and  a  respiratory  organ.  The 
liver,  the  head,  and  the  upper  extremities  are  large  in  the  fetus  because  the 
purely  arterial  blood  passes  to  these  organs.  The  other  viscera  and  the  lower 
extremities  are  small  because  the  blood  which  passes  to  them  is  practically 
venous. 

At  birth  the  placental  circulation  stops,  while  the  pulmonary  circulation 
is  increased  and  the  lungs  expand.  The  foramen  ovale  closes  about  the  tenth 
day  and  the  valvular  folds  adhers  to  its  margin.  As  said  before,  the  foramen 
ovale  remains  open  throughoul  life  in  one  case  ou1  of  five.  The  umbilical 
arteries  become  obliterated  beyond  the  bladder  in  from  two  to  five  days.  The 
umbilical  vein  and  ductus  venosus  dose  about  thesame  time  as  the  umbili- 
cal arteries.     The  ductus  arteriosus  closes  in  from  four  to  ten  days. 

\  plexus  i-  a  net-work.  (Plate  VI.)  The  Brachial  Plexus  is  a  net  work  of 
nerves  situated  in  the  axilla.     It  is  called  brachial  because  its  branches  supply 


A.NATOMY    IN    A    NUTSHELL.  35 

the  arm  or  brachium.     On  each  side  of  the  spinal  cord  are  five  plexuses,  making 

five  pairs  in  all.  We  learn  the  anatomy  of  the  lateral  half  of  the  body  and  the 
other  half  is  similar,  with  a  few  exceptions  in  the  viscera.  The  first  plexus  is 
made  of  the  anterior  divisions  of  the  first  four  cervical  nerves  and  is  called  the 
Cervical  Plexus.  The  next  plexus  in  order  is  called  the  Brachial,  and  is  com- 
posed of  the  anterior  branches  of  the  fifth,  sixth,  seventh  and  eighth  cervical 
nerves  and  part  of  the  first  dorsal  nerve.  In  the  dorsal  or  thoracic  region  there 
are  no  plexuses,  except  sympathetic.  There  are  plexuses  of  nerves  where  there 
is  much  work  to  be  done  by  the  nerves.  The  next  plexus  is  the  Lumbar  which 
is  composed  of  the  anterior  branches  of  the  first,  second,  third  and  part  of  the 
fourth  lumbar  nerves.  The  part  of  the  fourth  lumbar  nerve  which  does  not 
enter  into  the  formation  of  this  plexus  joins  the  fifth  lumbar  nerve  and  these 
two  nerves  make  the  lumbo-sacral  cord  which,  although  it  has  lumbar  nerves  in 
it,  belongs  to  the  sacral  plexus.  This  cord  with  the  anterior  divisions  of  the 
first,  second,  third  and  part  of  the  fourth  sacral  nerves  make  the  Sacral  Plexus. 
The  remaining  part  of  the  fourth  nerve  with  the  fifth  and  coccygeal  nerve,  make 
the  Coccygeal  Plexus.  As  the  spinal  cord  is  so  much  shorter  than  the  spinal 
canal,  the  nerves  leave  the  cord  above  the  foramina  where  they  leave  the  spinal 
canal. 

There  are  eight  cervical  nerves  although  only  seven  cervical  vertebra?,  as 
the  first  cervical,  or  suboccipital  nerve,  is  above  the  atlas  and  the  eighth  cervi- 
cal nerve  below  the  seventh  cervical  vertebra,  or  vertebra  prominens.  The 
eight  cervical  nerves  leave  the  cord  above  the  spinous  process  of  the  sixth  cer- 
vical vertebra. 

There  are  twelve  pairs  of  dorsal  or  thoracic  nerves;  the  first  six  of  these 
lea1,!'  the  cord  between  the  spinous  processes  of  the  sixth  cervical  and  the  fourth 
dorsal  vertebra;  the  lower  six  dorsal  or  thoracic  nerves  leave  the  cord  between 
the  spinous  processes  of  the  fourth  and  eleventh  dorsal.  The  five  Lumbar 
nerves  leave  the  cord  between  the  spinous  processes  of  the  eleventh  and  twelfth 
dorsal.  The  five  sacral  nerves  leave  the  cord  between  the  spinous  processes  of 
the  twelfth  dorsal  and  the  first  lumbar.  The  lower  nerve  roots  have  such  a 
long  course  between  the  cord  and  the  foramina  that  they  are  called  cauda  equina 
(horse  tail.) 


LESSON   VII. 

Clavicle  (Key.)— This  is  a  long  bone  but  it  has  no  medullary  canal  as  (he 
other  long  bones  have.  It  is  quite  elastic,  and  with  the  scapula  acts  ;is  a  cush- 
ion to  lessen  the  force  of  blows  upon  the  shoulder.  In  sonic  animals  it  does  not 
articulate  with  any  other  bone,  but  is  held  in  position  by  the  muscles.  This 
bone  and  the  scapula  make  the  shoulder  girdle.  It  is  present  in  those  animals 
which  have  claws  and  use  the  upper  or  front  extremity  for  other  purposes  than 
that  of  progression.  It  acts  as  a  fulcrum  for  t  he  various  movements  of  t  he  upper 
extremity.  It  is  situated  at  the  upper  anterior  part  of  the  chest,  between  the 
manubrium  of  the  sternum  and  the  acromion  process  of  the  scapula.  It  has  a 
double  curve  with  the  convexity  anterior  at  the  sternal  extremity  and  the  con- 


PLATE  VII. 


COMMON       CAROTID 


INNOMINATE  A. 


4      ':  ■ 


SUB-  CLAVIAN  VEIN  AND  ARTERY 


ANTERIOR    JUGOLCR- 


4NTERN6L       JUGULAR, 


EXTERNAL  JUGULAR. 


VENA-AZYGOS  MAJOR 


VENA  AZYGOS    TERTIUS. 

INTERCOSTAL  VEIN 
INTERCOSTAL  AJITEHT 
VENA-AZTGOS  MINOR. 


Relative  Position  of  Vwssles  Above  wi>  Below  the  Diaphragm. 


ANATOMY    IN    A    NUTSHELL.  37 

cavity  anterior  at  the  acromial  extremity.  It  is  more  often  broken  than  any 
other  bone  in  the  body  and  when  broken  will  press  upon  the  Brachial  Plexus 
producing  temporary  paralysis.  It  has  but  one  epiphysis,  which  is  at  the 
sternal  extremity,  hence  the  nutrient  artery  runs  towards  the  acromial  extrem- 
ity (Rule  2,  Lesson  1.)  The  bone  is  divided  into  an  inner  two-thirds 
which  is  somewhat  triangular  on  cross-section,  and  an  outer  one-third  which 
is  more  flattened  from  above  downward;  the  coracoid  process  of  the  scapula  is 
under  this  division  of  the  clavicle.     (Plates  X-XI.) 

Outer  one-third. — The  upper  extremity  of  this  portion  has  the  attachment 
of  the  Deltoid  muscle  in  front  and  the  Trapezius  behind,  with  a  small  interval 
between  them.  The  under  surface  has  first  a  conoid  tubercle  near  the  poster- 
ior border  and  internal  boundary  of  this  part  of  the  bone.  The  conoid  liga- 
ment passes  from  this  tubercle  to  the  coracoid  process  of  the  scapula,  which  is 
immediately  under  it.  Second,  the  trapezoid,  or  oblique  line,  sometimes  a 
furrow,  passes  from  the  conoid  process  forward  and  outward  and  gives  attach- 
ment to  the  trapezoid  ligament.  The  conoid  and  trapezoid  ligaments  make 
the  coraco-clavicular  ligament.  The  anterior  border  is  concave  and  gives  at- 
tachment to  the  Deltoid;  this  border  has  a  deltoid  tubercle.  The  posterior 
border  is  broader  than  the  anterior  one;  it  is  convex  and  gives  attachment  to 
the  Trapezius. 

Inner  two-thirds. — This  part  may  be  described  as  having  three  borders  and 
three  surfaces.  The  anterior  border  extends  from  the  anterior  border  of  the 
outer  one-third  to  the  inner  extremity  of  the  bone,  separating  the  anterior  and 
inferior  surfaces.  The  superior  border  extends  from  the  upper  part  of  the  pos- 
terior border  of  the  outer  one- third  to  the  inner  extremity  of  the  bone,  separat- 
um the  anterior  and  posterior  surfaces  of  the  clavicle.  The  posterior  border 
extends  from  the  conoid  tubercle  to  the  rhomboid  impression,  separating  the 
posterior  and  inferior  surfaces.  The  anterior  surface  gives  attachment  to  the 
Pectoralis  major  and  the  Sterno-cleido-mastoid  muscles.  The  posterior  sur- 
face gives  attachment  to  the  Sterno-hyoid  and  occasionally  the  Sterno-thyroid. 
It  has  a  nutrient  foramen  which  is  directed  outward  according  to  Rule  2, 
Lesson  ].  Sometimes  there  are  two  foramina,  one  of  which  may  be  mi  the 
inferior  surface.  The  inferior  or  subclavian  surface  has  near  its  inner  part  the 
rhomboid  impression  which  gives  attachment  to  the  costo-clavicular  or  rho- 
boid  ligament;  this  impression  is  about  as  inch  long.  The  subclavian  groove 
occupies  about  the  middle'  one-third  of  the  under  surface  of  the  clavicle  and 
gives  attachment  to  the  Subclavius  muscle.  The  sternal  extremity  is  triangu- 
lar, with  one  angle  above  and  two  below;  it  looks  inward,  downward  and  a 
little  forward.  It  is  convex  from  above  down  and  concave  antero-posterior- 
ily.  It  articulates  with  the  manubrium  and  its  circumference  is  rough  for  the 
attachment  of  the  ligaments  of  this  joint.  The  acromial  extremity  has  an  oval 
articular  facet  somewhat  convex,  which  is  directed  downward  and  forward  to 
articulate  with  the  acromion;  its  circumference  is  rough  for  the  attachment  of 
the  ligaments  of  this  joint.  The  righl  clavicle  is  longer,  thicker,  and  rougher 
than  the  left.  Those  of  the  male  are  longer,  thicker,  rougher  ami  more  curved 
than  those  of  the  female. 


38  ANATOMY    IN    A    NUTSHELL. 

Ossification.— Its  ossification  is  from  two  centers,  one  for  the  diaphysis, 
the  sixth  week,  or  may  be  as  early  as  the  thirtieth  day.  which  is  the  first  in  the 
body,  and  the  other  a1  the  sternal  extremity,  about  the  eighteenth  or  twen- 
tieth year,  complete  ossification  taking  place  about  the  twenty-fifth  year.  It 
begins  as  a  membranous  bone,  but  the  ossification  later  extends  into  the  under 
lying  cartilage. 

Articulation.  (Plate  XII.)  It  articulates  with  the  sternum,  the  cartilage 
of  the  first  rib  and  the  acromion  process  of  the  scapula.  The  sterno-olavicu- 
lar  articulation  is  a  reciprocal  reception  (saddle  shaped-joint,)  which  belongs  to 
the  diarthrodial  class  and  has  all  the  movements  except  rotation.  The  blood 
supply  of  this  joint  i: —  (1)  the  internal  mammary  from  the  subclavian.  (2) 
suprascapular  from  the  thyroid  axis.  (3)  superior  thoracic  from  the  first  portion 
of  the  axillary,  and  occasionally  twigs  from  a  muscular  branch  from  the  sub- 
clavian which  crosses  the  intersternal  notch.  The  nerve  supply  to  this  joint 
i~  ,  l  the  subclavian  from  the  Brachial  plexus  and  (2)  the  suprasternal  from 
the  Cervical  plexus.  The  ligaments  are  the  anterior  sterno-clavicular  ligament 
which  is  attached  to  the  upper  and  anterior  part  of  the  manubrium;  from  here 
it  passes  to  be  attached  to  the  upper  and  anterior  part  of  the  sternal  extremity 
of  the  clavicle.  The  posterior  sterno-clavicular  ligament  ha-  a  similar  attach- 
ment from  the  posterior  surfaces  of  the  same  hones.  These  two  make  the  cap- 
sular ligament.  The  interarticular  fibro-cartilage  is  thinner  in  the  center  than 
at  the  circumference  and  gives  attachment  to  the  sternal  end  of  the  clavicle 
above  and  the  firsl  costal  cartilage  at  its  junction  with  the  manubrium  below; 
thus  it  divides  the  synovial  membrane,  having  one  on  each  side. 

The  costo-clavicular  or  rhomboid  ligament  passes  upward,  backward  and 
outward  from  the  sternal  end  of  the  cartilage  of  the  first  rib  to  the  rhomboid 
impression  of  the  clavicle.  The  inter-clavicular  ligament  is  a  flat  cross-band 
attached  to  the  upper  margin  of  the  manubrium,  connecting  the  upper  parts 
of  the  inner  end-  of  the  clavicle. 

The  acromlo-clavicular  articulation  is  anarthrodial  joint.  (Plate  XIII.) 
The  blood  supply  is  (1)  the  suprascapular  from  the  thyroid  axis.  (2)theacromio- 
thoracic  and  (3)  posterior  circumflex.  The  nerve  supply  is  (1)  circum- 
flex from  the  posterior  cord  of  the  Brachial  plexus,  (2)  suprascapular,  from 
Brachial  plexus  and  (3)  supra-acromial  from  the  Cervical  plexns.  The  lig- 
aments  are  the  superior  acromio-clavicular  ligament,  a  quadrilateral  band 
which  passes  between  ihe  otiier  end  of  the  upper  surface  of  the  clavicle  and  the 
upper  surface  of  the  acromion  process.  The  inferior  acromio-clavicular  liga- 
ment covers  the  joint  below,  but  is  thinner  than  the  superior  one.  These  two 
make  the  capsular  ligament.  The  interarticular  fibro-cartilage  is  not  always 
present;  it  may  fill  the  articulation,  then  there  are  two  synovial 
membrane-;  more  often  it  only  occupies  the  upper  part  of  the  joint,  then  there 
i>  only  one  synovial  membrane.  The  trapezoid  ligament  is  the  anterior  and 
externa]  part  of  the  coraco-clavicular  ligament  and  is  attached  above  to  the 
oblique  line  of  the  under  surface  of  ihe  clavicle  and  below  to  the  posterior  half 
of  the  upper  surface  of  the  coracoid  process.  The  conoid  ligament  is  the  pos- 
terior and  internal  pari  of  ihe  coraco-clavicular  ligament  and  is  attached  above 


PLATE  IX. 


39 


40  ANATOMY    IX    A    NUTSHELL. 

by  its  base  to  the  conoid  tubercle  of  the  clavicle  and  a  line  running  internally 
for  half  an  inch:  below  by  its  apex  to  the  rough  impression  at  the  base  of  the 
coracoid  process. 

Blood  Supply.-  The  nutrient  artery  of  the  clavicle  is  from  the  supra- 
scapular. The  acromial  end  receives  a  branch  from  the  acromial  thoracic 
artery  and  twigs  from  the  arteries  in  the  muscles  attached  to  it. 


LESSON   VIII. 

Muscles. 

'The  muscles  of  the  clavicle  are  six.  viz.,  Sterno-cleido-mastoid.  Sterno- 
hyoid, Subclavius,  Pectoralis  major.  Deltoid,  Trapezius,  and  occasionally  the 
Sterno-thyroid. 

Sterno-cleido-mastoid;  Description. — (Plate  (XIV.)  This  muscle  passes 
obliquely  across  the  side  of  die  neck  and  is  enclosed  between  the  two  layers  of 
the  deep  cervical  fascia.  It  is  broad  and  thin  at  each  extremity,  hut  is  thicker 
mm. I  narrower  at  the  central  portion.  The  portion  which  is  attached  to  the 
sternum  is  directed  upward,  backward  and  outward.  This  attachment  is  ten- 
dinous  in  front  and  fleshy  behind.  The  portion  which  is  attached  to  the  clav- 
icle is  directed  almosl  vertically  upward  and  is  composed  of  fleshy  and  aponeu- 
rotic fibers.  These  two  portions  are  separated  at  their  origin,  but  become 
gradually  Mended  below  the  middle  of  the  neck  into  a  thick,  round  muscle. 
The  attachment  of  this  muscle  to  the  clavicle  may  he  as  small  as  the  sternal 
attachment  or  it  may  extend  to  the  attachment  of  the  trapezius  muscle  at  the 
outer  portion  of  the  clavicle.  This  muscle  divides  the  quadrilateral  space  at 
the  side  of  the  neck  into  two  triangles,  an  anterior  and  posterior. 

Origin.  By  two  heads;  first  from  the  anterior  surface  of  the  upper  part 
of  the  manubrium  of  the  sternum;  the  second  from  the  inner  one-third  of  the 
superior  border  ami  anterior  surface  of  the  clavicle.     (Plate  XI.) 

Insertion.  Mastoid  process  of  temporial  bone  and  the  outer  two-thirds 
or  one  half  of  the  superior  curved  line  of  the  occipital  bone. 

Action.     To  depress  and  rotate  head  and  elevate  the  thorax. 

Nerve  Supply.  Spinal  accessory  (eleventh  cranial)  and  deep  branches 
of  the  cervical  plexus  (second  and  (third'.')  nerves.) 

Blood  Supply.  The  superior  sterno-mastoid  artery  from  the  occipital 
artery,  the  middle  sterno-mastoid  artery  from  the  superior  thyroid  artery,  the 
inferior  sterno-mastoid  artery  from  the  suprascapular  artery,  also  branches 
from   the  posterior  auricular  artery. 

Sterno-hyoid.  Description.  The  sterno-hyoid  covers  the  thyroid  gland 
and  upper  pari  of  the  trachea,  and  is  a  thin  narrow  muscle,  its  lower  portion 
being  immediately  beneath  the  Sterno-mastoid.  This  muscle  comes  in  contact 
with  its  fellow  in  the  middle  of  their  course,  and  from  there  on  lie  side  by  side, 
but  they  are  separated  below  from  each  other  by  a  considerable  interval. 

Origin,  i  1  i  Posterior  surface  of  the  manubrium  of  the  sternum.  (2)  ster- 
nal end  of  the  clavicle  and  posterior  sterno-clavicular  ligament. 


ANATOMY    IX    A     XUTSUhLL. 


41 


Insertion. — Body  of  the  hyoid  bone.      (Plate  XIX.) 
Action. — To  depress  the  hyoid  bone. 

Nerve  Supply. — Branches    from    Loop   of   communication     between    the 
cervical  plexus  and  the  twelfth  cranial  nerve. 


TUBEROSITY  FOR  CONOID  LI  GMT 

OBLIQUE  VINE   FOR 
TRAPEZOID  LICKT. 


PLATE  X. 

—  POSTERIOR 
SUBCLAVIU5 


STERNO-THYROiD. 
STERNO  HYOID. 


ARTIC. 
WITH  THE 
SCAPULA. 


capsular  lkvm-t  pectoral1s  major. 

anterior. 

Left  Clavicle.     Ixferioh  Surface. 


Blood  Supply. — Lingual,  inferior  and  superior  thyroid  arteries. 

Sterno-thyroid. — Origin.  —  (1)  Posterior  surface  of  the  manubrium  of  the 
sternum  and  the  cartilage  of  the  first  rib,  occasionally  from  the  second  rib  and 
_'     -ometimes  from  the  clavicle. 

Insertion. — Oblique  line  of  ala  of  thyroid  cartilage. 

Action. — Depressor  of  larynx. 

Nerve  Supply. — Branches  from  the  loop  of  communication  between  the 
cervical  plexus  and  the  twelfth  cranial  nerve. 

Blood   Supply. — Lin qual,  inferior   and   superior   thyroid   arteries. 

PLATE  XL 

-ANTERIOR. 

PECTORALIS 

MAJOF 


acromial  end 

trapezius 

—  posterior.- — 
Left  Clavicle.     Superior  Surface. 

Pectoralis  major. — Description. — (Plate   XV.)-    This   muscle   is  situated 

in  front  of  the  axilla,  also  on  the  upper  and  foreparl  of  the  chest.  P  is  trian- 
gular, being  both  broad  and  thick.  From  it s  origin  the  fibers  nil  pa--  towards 
its  insertion,  giving  it  the  shape  of  a  fan.  tts  tendon,  which  i-  flat,  is  aboul 
two  inches  in  breadth.  The  tendon  i>  made  of  two  layers  placed  one  in  front 
of  the  other  and  usually  blended  together  below.  The  anterior  layer  which  is 
thicker  receives  the  clavicular  and  upper  half  of  the  sternal  portion  of  the  mus- 
cle and  its  fibers  are  inserted  in  the  same  order  a-  that  in  which  they  arise.     The 


42  ANATOMY    JX    A    NUTSHELL. 

rior  layer  of  the  tendon  receives  the  attachment  of  the  lower  half  of  the 
sternum  and  the  deeper  pari  of  the  muscle  from  the  costal  cartilages.  These 
deep  fibers,  and  particularly  those  of  the  lower  costal  cartilages  ascend,  the 
higher  turning  backward  successively  behind  the  superficial  and  upper  ones,  so 
thai  the  tendon  appears  to  be  twisted.  The  posterior  layer  reaches  higher  on 
the  humerus  than  the  anterior  one  and  from  it  an  expansion  is  given  off  that 
covers  the  bicipital  groove  and  blends  with  the  capsule  of  the  shoulder- joint. 
An  expansion  is  given  off,  which  lines  the  bicipital  groove,  from  the  inseriton 
of  the  deeper  fibers.  An  expansion  passes  downward  to  the  fascia  of  the  arm 
from  the  lower  part  of  tendon.  This  muscle  is  separated  from  the  Deltoid  by 
slight  interspaces  in  which  lie  the  cephalic  vein  and  the  humeral  branch  of  the 
acromio-thoracic  artery.      Its  border  forms  the  anterior  margin  of  the  axilla. 

ORIGIN.  —  (1)  The  anterior  surface  of  the  sternal  half  of  the  clavicle.  (2) 
Half  the  breadth  of  the  anterior  surface  of  the  sternum  as  far  down  as  the 
attachment  of  the  cartilages  of  the  sixth  and  seventh  ribs.  (3)  Cartilages  of 
all  the  true  ribs,  excepting  the  first  and  seventh,  or  both,  and  aponeurosis  of 
the  External  oblique  of  the  abdomen.     (Plate  XI.) 

Insertion.  The  fibers  which  arise  from  the  the  clavicle  pass  obliquely 
outward  and  downward:  those  from  the  lower  part  of  the  sternum  and  cartil- 
ages of  the  lower  true  ribs  upward  and  outward,  whilst  the  middle  fibers  pass 
horizontally.  The  tendon  of  termination  is  inserted  into  the  outer  bicipital 
ridge  of  the  humerus.     (Plate  XXIII.) 

Action.  Draws  the  arm  forward  and  downward,  also  elevated  the  ribs 
in  forced  inspiration. 

\'i.i;\  e  Si  ri  ia  .  ---  External  and  internal  anterior  thoracic.  The  nerves  receive 
filaments  from  all  spinal  nerves  entering  into  the  format  ion  of  the  brachial  plexus. 

The  costo-coracoid  membrane  is  a  strong  fascia  situated  in  the  interval 
between  the  Pectoralis  minor  and  Subclavius muscles  and  protects  the  axillary 

els  and  nerves.  It  divides  above  to  enclose  the  Subclavius  muscle  and  its 
two  layers  are  attached  to  the  clavicle,  one  in  front  of  and  the  other  behind 
the  muscle.  The  latter  layer  fuses  with  the  deep  clavicular  fascia  and  with 
fascia  of  the  axilla r\  vessels.  Internally,  it  blends  with  the  fascia  covering 
the  firsl  two  intercostal  spaces  and  is  also  attached  to  the  first  rib,  internal  to 
the  < » r i - i 1 1  of  the  Subclavius  muscle.  Externally  it  is  very  thick  and  dense  and 
is  attached  to  the  coracoid  process.  This  membrane  is  pierced  by  two  arteries, 
two  nerves,  and  two  veins.  The  superior  and  acromial  thoracic  arteries,  the 
external  and  internal  anterior  thoracic  nerves,  and  the  acromial  ihoracic  and 
cephalic  veins. 

Blood  Supply.  Internal  mammary,  intercostals,  superior  thoracic, 
acromial    thoracic,  am!   long  thoracic. 

LESSON   VIII. 
Subclavius.     (Plate  XV).     Des<  ription.-  This  is  a  small  triangular  mus- 

•le  placed  in  the  interval  between  the  clavicle  ami  the  firsl  rib.  It  is  separated 
from  the  firsl  rib  by  the  subclavian  vessels  and  brachial  plexus  of  nerves.  Its 
interior  surface  i-  separated  from  the  Pectoralis  major  by  the  costo-coracoid 
membrane,  which  with  the  clavicle,  forms  an  osseo-fibrous  sheath  in  which  the 


ANATOMY    IN    A    NUTSHELL. 


43 


muscle  is  enclosed.     The  insertion  of  this  muscle  is  larger  than  the  origin. 

Origin. — By  strong  tendon  from  the  first  rib  and  its  cartilage  at  their 
junction  in  front  of  the  rhomboid  ligament. 

Insertion. — Under  surface  of  the  clavicle  in  a  deep  groove  about  its  middle 
third.     (Plate  XL) 

Action. — Depresses  shoulder  by  drawing  the  clavicle  downward  and  for- 
ward. 

Nerve  Supply. — Filaments  from  the  fifth  and  sixth  cervical. 

Blood  Supply. — First  intercostal  and  short  thoracic  arteries. 

Deltoid.— Description.— (Plates  XYIII-XIY-XY-XYI.  i— The  Deltoid  is 
a  triangular  muscle  which  gives  the    rounded  outline  to  the  shoulder.      It  i- 

PLATE  XII. 

ANTERIOR     STERNO-CLAUCULAR  LIGAMENT 


THE  INTERARTICULAR     FIBRO-CARTILAGE 


THE     JOINT     BETWEEN  THE  STERNUM 
A\D  SECOND  COSTAL    CARTILAGE 


Sterno-Claviculak  Articulation. 


large  and  thick.  It  surrounds  the  shoulder-joint  in  the  greater  part  of  its 
of  its  extent,  covering  it  on  it-  outer  >ide  and  in  front  and  behind.  It-  •: 
surface  is  separated  from  the  head  of  the  humerus  by  a  large  sacculated  syn- 
ovial bursa.  It-  anterior  border  i-  separated  at  its  upper  part  from  the  Pec- 
toralLs  major  by  a  cellular  interspace  which  lodges  the  cephalic  vein  and  the 
humeral  branch  of  the  acromial  thoracic  artery.  This  muscle  i-  remarkably 
coarse  in  its  texture. 

Origin.— (Plate.-  XI-XX.>  —  (1)  Outer  thiol  of  anterior  border  and  upper 
surface  of  clavicle.     (2)  Outer  margin  and  upper  surface  of  acromion  proc< 
(3)   Lower  lip  of  posterior  border  of  -pine  of  scapula  as  far  back  as  the  trian- 
gular surface  at  the  inner   end.     The  part   arising  from  the  acromion  process 


44 


ANATOMY    IX   A    NUTSHELL. 


consists  of  oblique  fibers  which  arise  in  a  bipenniform  manner  from  the  sides 
of  tendinous  intersections,  generally  four  in  number,  which  are  attached  above 
id  the  acromion  process  and  pass  downward  parallel  t<>  one  another  in  the  sub- 
stance  of  the  muscle.  The  portion  of  the  muscle  which  arises  from  the  clavicle 
and  the  -pine  of  the  scapula  are  no1  arranged  in  this  manner,  bu1  pass  directly 
from  i heir  origin  to  their  insertion. 

Insertion.  (Plate  XXIII.)  The  fibers  of  this  muscle  converge  to- 
wards their  insertion,  the  middle  passing  vertically,  the  anterior  obliquely 
backward,  and  the  posterior  obliquely  forward;  they  unite  to  form  a  thick  ten- 


PLATE  XIII 


TRANSVERSE  LIGAMENT 


Acromio-Clavicular  Articulation  and  Shoulder-Joint. 


don  which  is  inserted  into  a  rough  triangular  prominence  on  the  middle  of  the 
outer  side  of  the  shafl  of  the  humerus.  At  its  insertion  is  given  oft'  an  expan- 
sion t<>  the  deep  fascia  of  the  arm.  The  oblique  filters  arising  from  the  tendi- 
nous intersections,  generally  three  in  number,  pass  upward  from  the  intersec- 
tion of  the  muscle  ami  alternate  with  the  descending  septa. 

Action.     To  raise  the  arm  ami  helps  to  draw  it  forward  ami  backward. 

Xi.i;\  i.  Si  ppli      ( Jircumfiex. 

Blood  Supply.    rPosterior  circumflex  ami  acromial  thoracic  arteries. 


ANATOMY    IX    a    NUTSHELL.  45 

Trapeszius. — Description.  —  (Plate  XVIII.)  This  is  a  broad,  Hat.  trian- 
gular muscle,  placed  immediately  beneath  the  skin  and  fascia,  and  covering 
the  upper  and  back  part  of  the  neck  and  shoulders.  It  is  fleshy  in  the  •:• 
part  of  its  extent,  but  tendinous  at  its  origin  and  insertion.  At  its  origin,  from 
the  spines  of  the  vertebrae,  it  is  connected  to  the  bones  by  means  of  broad  semi- 
elliptical  aponeurosis,  which  occupies  the  space  between  the  sixth  cervical  and 
the  third  dorsal  vertebra,  and  tonus,  with  the  aponeurosis  of  the  opposite  side, 
a  tendinous  ellipse. 

Origin. — (1)  by  thin  fibrous  lamina'  from  the  external  occipital  protuber- 
ance and  the  inner  one-third  or  one-half  of  the  superior  curved  line  of  the  occipi- 
tal bone.  (2)from  the  ligamentum  nuchas.  (3)from  spinous  processes  of  the  seventh 
cervical  and  all  the  dorsal  vertebra11  (4)  and  from  the  corresponding  portion  of 
the  supraspinous  ligament. 

Insertion — (PlateXI-XX) — Thesuperior  fibers  pass  downward  and  out- 
ward and  are  inserted  into  the  outer  one- third  of  the  posterior  border  of  the  clavicle 
varing  greatly  in  the  extent  of  its  attachment,  sometimes  advancing  as  far  as 
the  middle  of  the  clavicle,  and  may  even  become  blended  with  the  posterior 
edge  of  the  Sterno-mastoid  oroverlapingit.  The  middle  fibers  pass  horizontally 
outward  and  are  inserted  into  the  inner  margin  of  the  acromion  process  and 
superior  lip  of  the  posterior  border  or  crest  of  the  spine  of  the  scapula.  The 
inferior  fibers  pass  upward  and  outward,  converging  near  the  scapula,  and  ter- 
minate in  a  triangular  aponeurosis  which  glides  over  a  smooth  surface  at  the 
inner  extremity  ofthe  spine,  to  be  inserted  into  a  tubercle  at  the  outer  part  of 
this  smooth  surface. 

Action". — When  this  muscle  acts  as  a  whole  it  lifts  the  shoulder  ami  ro- 
tates the  lower  angle  of  the  scapula  outward.  The  upper  part  raises  the  shoulder, 
the  middle  part  draws  it  toward  the  spine,  and  the  lower  pan  in  pulling  the 
scapula  down  and  inward  tilts  the  acromion  process  upward.  If  the  shoulder 
girdle  i>  fixed,  this  muscle  will  draw  the  head  backward. 

Nerve  Supply. — Spina!  accessory  and  third  and  fourth  cervical. 

Blood  Supply. — Princeps  cervicis  from  occipital,  superficial  cervical  ami 
posterior  scapular  from   transversalis  colli. 


LESSON   IX. 

Scapula  (Spade.)— (Plates  XX-XXI.) — The  scapula  makes  the  posterior 
pari  of  the  shoulder-girdle,  h  is  situated  on  the  upper  posterior  part  of  the 
thorax,  between  the  second  lib  above  and  the  seventh  or  eighth  ribs  below, 
articulating  with  the  clavicle  by  its  acromion  process  laterally.  'This  bone  is 
made  up  of  several  triangles;  first,  the  main  pari  of  the  bone  i>  triangular  with 
two  angles  above  and  one  below;  the  one  n<  \t  to  the  vertebral  column  is  called 
the  superior  angle;  the  one  n<  ar<  s1  the  clavicle  is  called  the  anterior  or  external 
angle  and  articulates  with  the  humerus;  the  one  near  the  seventh  or  eighth  rib 
is  the  inferior  angle.  Being  a  triangle  it  will  have  two  surfaces  and  three  bor- 
ders, as  well  as  three  angles.  The  anterior  surface  or  venter  is  concave,  deepest 
where  the  upper  one-fourth  joins  the  lower  three-fourths;  this  is  to  give  more  room. 


{li  WATOMY    JX    A    NUTSHELL. 

for  the  Subscapulars  muscle;  this  surface  is  also  called  the  subscapular  fossa- 
On  this  surface  there  arc  several  oblique  lines  running  from  the  vertebral  bor- 
der upward  and  outward,  for  the  attachment  of  the  fascia  of  the  Subscapulars. 
The  vertebral  asped  of  this  surface  gives  attachment  to  the  Serratus  magnus, 

which  attachment  is  triangular  above  and  below  with  a  long  narrow  attach- 
ment between.  The  posterior  surface,  or  dorsum,  as  a  whole  is  convex.  It  is 
separated  into  two  parts  by  a  second  triangle,  which  is  called  the  spine  of  the 
scapula.  The  part  above  the  spine  is  called  the  supraspinous  fossa  and  is  for 
the  Supraspinatus muscle,  and  the  part  below  is  the  infraspinous  fossa  and  is 
I'm-  the  Infraspinatus  muscle.  'This  spine  separates  the  upper  one-fourth  from 
the  lower  three-fourth-  opposite  the  deepest  part  of  the  subscapular  fossa. 
The  superior  border  is  the  shortest  and  has  a  notch  called  the  suprascapular 
notch,  which  i-  about  at  the  junction  of  the  external  one-third  with  the  in- 
ternal two-thirds.  This  notch  transmits  the  suprascapular  nerve  and  is  crossed 
by  the  transverse  ligament  of  the  scapula.  The  outer  extremity  of  this  border 
i-  continued  as  the  coracoid  process  which  may  be  called  a  third  triangle  or 
rather  pyramid;  it  gives  attachment  to  three  muscles,  the  short  head  of  the  Bi- 
ceps,  Coraco-brachialis,  and  Pectoralis  minor.  The  vertebral  or  posterior  bor- 
der  is  the  longest  and  i.-  called,  the  base;  it  has  three  muscles  attached  to  it,  the 
Levator  anguli  scapulae,  and  the  Rhomboideus  minor  and  major.  The  axillary 
border  is  the  thickest  of  the  three  and  would  be  the  longest  of  the  borders  if 
it  were  continued  to  meet  the  superior  bonier.  It  has  three  muscles  attached, 
i  he  Teres  major  and  minor  and  the  long  head  of  the  Triceps.  Then  with  the 
axillary  border  continued  to  meet  the  superior  border  we  have  a  triangle  whose 
base  is  the  vertebral  border,  whose  altitude  is  the  superior  border  and  whose 
hypotenuse  is  the  axillary  border  continued,  and  in  this  case  would  be  the 
longest.  There  is  a  groove  on  the  axillary  border  at  the  junction  of  the  upper 
one-third  with  the  lower  two-thirds,  for  the  dorsalis  scapulae  artery,  and  an 
oblique  line  separating  the  attachments  of  the  Teres  minor  and  major.  The 
spine  represented  a-  a  triangle  will  have  its  base, the  anterior  border, attached 
io  the  dorsum  of  the  scapula  from  a  point  about  one-fourth  the  distance  from 
the  vertebral  border  to  the  glenoid  fossa  to  within  half  an  inch  of  the  glenoid 
fossa;  the  portion  between  the  spine  and  the  glenoid  fossa  is  the  great  scapular 
notch.  The  glenoid  fossa  is  the  deficiency  between  the  superior  and  axillary  borders, 
with  which  the  head  of  the  humerus  articulates.  The  altitude  is  the  external 
border,  called  by  some    author.-  the  base;  the  posterior  border  or  crest  repre- 

■  the  hypontenuse  of  the  triangle.  The  crest,  posterior  border,  or  hypo- 
tenuse is  continued  outward  a-  t he  acromion  process  of  the  scapula  and  is  some- 
what  triangular.  Its  upper  lip  gives  attachment  for  the  Trapezius  and  the 
lower  lip  to  the  Deltoid  muscle.  This  process  articulates  with  the  clavicle  and 
gives  attachment  for  theligaments  of  that  articulation,  beside-  to  the  coraco- 
acromial  ligament,  between  the  spine  of  the  scapula  and  the  vertebral  border 
is  a  smooth  surface  for  the  Trapezius  to  glide  over. 

Ossification.  The  scapula  ha-  seven  centers  of  ossification,  occasionally 
it  has  nine  center-.  One  for  the  body  of  the  scapula  makes  its  appearance  about 
the  eighth  week  of  intrauterine  life;  the  one  for  the  posterior  border  and  also 


PLATE  XIV 


|  -  OCCIPITO    FRONTALIS. 

2  -  ORBICULARIS  PALPEBRARUM. 

3  -  CORRUGATOR    SUPERCIlll. 
4-  PYRAVUOALIS. 

5  -  COMPRESSOR    NAR1S. 

6  -  COMPRESSOR  NARIUM  MINOR. 

7  -  DILATOR  NARIS  ANT. 

8  -DILATOR 

NARIS  POST 

9  -  DEPRESSOR 

ALA  NAS 
10- LEVATOR 
LABIISUP. 
ALfcQUE 
NASI. 


31-STERNO  CLEIOO  MASTOID. 
32-STERNO   HYOID 
33-OMO    HYOIO. 
34-THYRO    HYOID. 


35-  STERNO  THYROID 

36-  INF.  CONSTRICTOR. 

37-  SCALENUS  MEDIUS. 
SCALENUS  POSTICUS 
LEVATOR  ANGULI    SCAPUL/t. 
SPLENIUS  CAPITIS  ET-COLLI. 

41-TRAPEZIUS. 

42-APONEUROSIS 

43 -EXT.  LATERAL  LI  G 
44- HYOID  BONE 
4S-ZYG0MA. 
46  INF.MAXILARV. 
47    CLAVICLE. 

48  PECTORALIS 
MAJOR. 
49  DELTOID. 


II  -  LEVATOR 

LABII-SUP.PROP. 

12-LEVATOP  ANGUL 
I3-2YGOMAT1CUS  MINOR. 
I4-2YG0MATICUS  MAJOR. 
15 -ORBICULARIS  ORIS. 
16-  RISORIUS. 
17 -BUCCINATOR. 
18-MASSETER. 
19-  LEVATOR  LABII  INF. 
20- DEPRESSOR  LABII  INF. 
2I-0EPRESSOR  ANCULI  ORIS. 
22-  PLATYSMA-MYOIDES. 
23-ATTRAHENS  AUREM. 
24- ATTOLENS  AUREM. 
25-RETRAHENS  AUREM 
26- DIGASTRIC. 
27- STYLO    HYOIO. 
2S-MYL0-HY0ID. 
29-HYO-GLOSSUS. 
30- MID.  CONSTRICTOR 


W* 


Muscles  ok  Face   \ \i>  'I'.m  vngli 
17 


i  !■'    N  I  I    K 


is  ANATOMY    IX    A    NUTSHELL. 

the  one  for  the  inferior  angle  appear  aboul  the  15th  year  and  join  the  body  of 
the  scapula  the  25th  year.  There  are  two  for  the  acromion  process  which  ap- 
pear the  l">tli  year  and  join  the  body  of  the  scapula  the  20th  year.  The  cor- 
acoid  process  has  two  centers,  the  one  a1  the  base  of  the  process  appearsatthe 
linh  year  and  the  other  during  the  1st  year;  they  both  join  the  body  of  the  scap- 
ula the  25th  year. 

Articulation.  It  articulates  with  the  clavicle,  (a  description  of  which  is 
given  in  Lesson  Vll.)  and  with  the  humerus,  making  the  shoulder-joint.  This 
joint  is  a  diarthro dial  joint  and  belongs  to  the  sub-class  enarthrodial  (ball-and- 
socket.)     Plate  XIII.) 

Blood  supply  of  the  shoulder-joint  is  ( 1 )  suprascapular  from  the  thyroid 
axis,  ('_)  anterior  circumflex,  (3)  posterior  circumflex,  and  (4)  subscapular. 
The  last   three  are  from  the  third  part  of  the  axillary  artery. 

Nerve  supply.  (1)  Suprascapular  and  (2)  circumflex,  both  are  branches 
formthe   Brachial  plexus. 

Ligaments.  The  true  ligaments  of  the  scapula  are  the  transverse  or  supra- 
scapular which  passes  o\cr  the  suprascapular  notch  separating  the  suprascap- 
ular nerve  from  the  suprascapular  vessels  above.  The  coraco-acromial  lig- 
ament, which  is  triangular,  is  attached  by  its  base  to  the  entire  outer  border  of 
the  coracoid  process,  and  by  its  apex  to  the  tip  of  the  acromion  process. 

The  ligaments  of  the  shoulder- joint  are  (1)  The  capsular  which  is  very 
loose  and  permits  free  movements  of  the  joint.  It  is  attached  to  the  circum- 
ference of  the  glenoid  cavity  and  to  the  anatomical  neck  of  the  humerus.  This 
is  thickesl  above.  It  may  have  three  openings  in  it.  one  for  the  long  head  of 
i  he  Biceps  between  the  two  tuberosities,  another  below  the  coracoid  process, 
partially  filled  by  the  tendon  of  the  Subscapulars  and  a  third  (which  is  not 
always  present)  for  the  tendon  of  the  Infraspinatus  muscle.  These  openings 
are  for  the  communication  between  the  synovial  membranes  of  the  joint  and 
the  bursa'  beneath  the  tendons.     A  bursa  is  a  sac  or  pouch. 

The  long  head  of  the  Biceps  is  a  ligament.  On  the  inner  and  anterior  as- 
pect of  the  capsular  ligament  are  three  gleno-humeral  ligaments,  thickened 
portions  of  the  capsular  ligament,  (a)  The  upper  one  of  these  is  called  Flood's 
ligament,  (b)  the  middle  one  is  the  interna]  brachial  of  Schlemm  and  (e)  the 
inferior  is  called  the  broad  ligament  of  Schlemm.  (2)  The  coraco-humeral 
or  accessory  ligament,  is  also  a  part  of  the  capsular  ligament;  it  is  attached  to 
the  outer  border  of  the  base  of  the  coracoid  process  above  and  to  the  ureal 
tuberosity  of  the  humerus  below.  (3)  The  transverse  ligament  passes  over  the 
bicipital  groove,  holding  down  the  long  head  of  the  Biceps.  (4)  The  glenoid 
I  i 'j  a  men  i  i-  a  continuation  of  the  long  head  of  the  Biceps  which  makes  the  glenoid 
fossa  deeper  ;i 1 1 •  1  it  join.-  the  long  head  of  the  Triceps  below.  It  is  narrow  at 
tin'  circumference,  but  broad  at  its  base.  It  is  a  fibro-cartilaginous  rim.  A 
synovia!  membrane  lines  these  joints  ami  is  reflected  through  the  opening  in 
the  capsule  and  oxer  the  long  head  of  the  Biceps  in  the  groove. 


PLATE  XV 


MEDIAN  NERVE. 
RACHIAL  ARTERY 

Mk BSSIL.C  .; 


BRACHIAUS  AMICUS. 


SUPINATOR  LONGUS 


External  Oblique  Muscle  of  Abdomen  and  Numerous  other  Structures. 

19 


50  ANATOMY    IN    A    NUTSHELL 

LESSON  X. 

Mus<  i.i.-.     There  are  seventeen  muscles  attached  to  the  scapula. 
Three  to  the  vertebral  border-      Three  to  the  fossae — 

Levator  anguli  scapulae;  Supraspinatus — in  the  supraspinous 

Rhomboideus  minor;  fossa-; 

Ethomboideus  major.  Infraspinatus — in  the  infraspinous 

TWO    L'O  A(  ROMION    PRO<   ESS —  fossa; 

Trapezius;.  Subscapularis— in  the  subscapular 

Deltoid.  fossa. 

Three  to  the   axillary  bori>eh        Three  to  the  coracoid  process — 
Long  head  of  the  Triceps;  Short  head  of  Biceps; 

Teres  minor:  Coraco-brachialis ; 

Teres  major.  Pectoralis  minor. 

Three  irregularly  arranged — 

Omo-hyoid,  near  transverse  ligament; 

Serratus  magnus,  on  the  vertebral  aspect  of  the  venter; 

Latissimus  dorsi,  on  the  interim'  angle,  dorsal  aspect. 

When  all  the  muscles  of  the  clavicle  ami  scapula  are  uiven.  we  have  all  the 
muscles  in  the  upper  extremity  as  far  as  the  elbow,  except  the  Brachialis  an- 
ticus.     (Plate  XVI.) 

Pectoralis  minor.  —  Description. — (Plate  XVI.) — This  is  a  thin.  flat,  tri- 
angular muscle  situated  at  the  upper  part  of  the  thorax  beneath  the  Pectoralis 
major.  Its  upper  border  is  separated  from  the  clavicle  by  a  triangular  inter- 
val, broad  internally,  narrow  externally,  which  is  occupied  by  the  costo-cor- 
acoid  membrane.  In  this  space  is  the  first  part  of  the  axillary  vessels  ami 
nerves.  Running  parallel  to  the  lower  border  of  the  muscle  is  the  long  thoracic 
artery. 

Origin.  —Upper  margin  ami  outer  surface  of  the  third,  fourth  and  fifth 
ribs  near  cartilages,  and  aponeurosis  covering  the  Intercostal  muscles. 

Insertion.  The  fillers  converge  and  form  a  flat  tendon  which  is  inserted 
into  the  inner  horde!'  and  upper  surface  of  the  coracoid  process  of  the  scapula. 
(Plate    XXI.) 

Action.-  To  depress  the  point  of  the  shoulder  and  aids  in  forced  inspira- 
tion. 

Nerve  Si  pply.  -Internal  anterior  thoracic,  the  filaments  being  derived 
from  the  eighth  cervical  and  first   dorsal  nerves. 

Blood  Supply  is  from  the  internal  mammary,  intercostals,  superior  thor- 
acic, acromial  thoracic,  and  long  thoracic. 

Triceps.  Description.  (Plate  XVIII.)— The  Triceps  is  situated  at  the 
hack  of  the  arm.  extending  the  entire  length  of  the  posterior  surface  of  the 
humerus.  It  is  of  large  size  and  divided  above  into  three  parts,  hence  its  name. 
The-.-  portions  have  been  named  (1)   the  middle,  scapular,  or  long  head;  (2) 


PLATE  XVI 


OF    BICEPS    ANO    COMCO  BRtCMIA 


CUTANEOUS  NERV. 


^PRONATOR  RAOM  TERES 


Internal  Oblique  Muscle  of  Abdome 

51 


OMEN  AND 


Numerous  Other  Structures 


52  ANATOMY    IN    A    NUTSHELL. 

the  external,  or  long  humeral;  and  (3)  the  internal,  or  short  humeral  head. 
The  common  tendon  of  the  Triceps  commences  about  the  middle  of  the  back 
part  of  the  muscle;  it  consists  of  two  aponeurotic  lamina',  one  of  which  is  sub- 
cutaneous  and  covers  the  posterior  surface  of  the  muscle  for  the  lower  half  of 
it-  extenl  :  the  other  is  more  deeply  seated  in  the  substance  of  the  muscle.  After 
receiving  the  attachment  of  the  muscular  fibers  they  join  together  above  the 
elbow,  forming  the  tendon  of  Insertion.  A  small  bursa  is  situated  beneath  the 
tendon. 

Origin.-  The  middle  or  long  head  arises  from  a  rough  triangular  depres- 
sion on  the  scapula,  just  below  the  glenoid  cavity,  being  blended  at  its  upper 
part   with  the  capsular  ligament.     (Plate  XXI.) 

The  external  head  arises  from  the  posterior  surface  of  the  shaft  of  humerus, 
between  the  insertion  of  the  Teres  minor  and  the  upper  pari  of  the  musculo- 
spiral  groove;  also  from  the  external  border  of  the  humerus  and  external  in- 
termuscular septum.     (Plate  XXII.) 

The  internal  head  arises  from  the  posterior  surface  of  shaft  of  humerus, 
below  the  groove  for  the  musculo-spiral  nerve,  extending  from  the  insertionof 
the  Teres  major  to  within  an  inch  of  the  trochlear  surface;  also  from  the  internal 
borderof  the  humerus  andfrom  the  back  of  the  whole  length  ofthe  internal  and 
lower  part   of  the  external   intermuscular  septum.      (Plate  XXII.) 

Insertion.-  Upper  end  of  olecranon  process  of  ulna,  a  band  of  fibers  being 
continued  downward  to  blend  with  the  deep  fascia  of  forearm.     (Plate  XXIV.) 

Action-  Extensor  of  forearm. 

Nerve  Supply-    Seventh  and  eighth  cervical  through  musculo-spiral. 

Blood  Si  pply — Brachial  and  superior  profunda. 

Latissimus  dorsi. — Description. — (Plate  XYIII.) — This  is  a  broad,  flat 
muscle  which  rovers  the  lumbar  and  lower  half  of  the  dorsal  regions  and  is 
gradually  contracted  into  a  narrow  fasciculus  which  passes  upward  across  the 
interior  angle  of  the  scapula,  and  occasionally  receives  a  few  fibers  from  it.  It 
belongs  to  the  first  layer  of  muscles  in  the  back. 

The  muscle  then  curves  around  the  lower  border  of  the  Teres  major,  and  is 
twisted  upon  itself.  It  terminates  in  a  short,  quadrilateral  tendon,  about  three 
inches  in  length,  which,  as  it  passes  in  front  of  the  tendon  of  the  Teres  major 
becomes  united  with  it.  the  surfaces  of  the  two  being  separated  by  a  bursa; 
another  bursa  is  sometimes  interposed  between  the  muscle  and  the  inferior 
angle  of  the  scapula.  At  the  insertion  of  this  muscle  an  expansion  is  given  off 
to  the  deep  fascia  of  the  arm.  There  IS  usually  a  fibrous  slip  which  passes  from 
the  lower  border  of  the  tendon  of  the  Latissimus  dorsi.  near  its  insertion,  to  the 
long  head  of  die  Triceps.  This  is  occasionally  muscular  and  is  the  representa- 
tive of  the  Dorso-epitrochlearis  muscle  of  apes. 

Origin.  From  the  spinous  processes  of  die  six  inferior  dorsal  vertebra?, 
and  from  the  posterior  layer  of  the  lumbar  fascia,  by  which  it  is  attached  to  the 
spines  of  die  lumbar  ami  sacral  vertebrae,  and  to  the  supraspinous  ligament, 
also  from  the  external  lip  of  the  cresl  of  the  ilium  behind  theorigin  of  the  ex- 
ternal oblique,  and  bv  fleshy  digitations  from  the  three  or  four  lower  ribs,  which 


PLATE  XVI] 


5TH  CElWlCAL  N 
6TH  CERVICAL  N. 
7TH    CERVICAL  N 


ACROM'AL  THORACIC. 


LR  CORO. 


ANT.  CIRCUMFLEX. 


-POST.  CIRCUMFLEX. 


SUPERIOR  PROFUNDA. 


DIGITAL  BRANCHES. 


B         DCPSALIS 


Transversalis  Muscle  op  Abdomen  \\i>  Numerous  Otheb  Structures 

53 


54  ANATOMY    IN    A     NUTSHELL. 

are  interposed  between  similar  processes  of  the  External  oblique  muscle.  The 
upper  fibers  pass  longitudinally  outward,  the  middle  fibers  obliquely  upward, 
and  ihc  lower  fibers  vertically  upward,  converging  at  the  inferior  angle  of  the 
scapula.     ( Plate  XX.) 

Insertion.-  Into  the  bottom  of  the  bicipital  groove  of  the  humerus,  its 
insertion  extending  higherthan  that  of  the  Pectoralis  major.     (Plate  XXIII.) 

A'  riON.-  Draws  the  arm  down  and  hack,  raises  the  lower  ribs,  and  draws 
the  trunk  forward. 

Nerve  Supply.-    Middle  or  long  subscapular. 

Blood  Supply.     Subscapular  artery. 

Serratus  magnus. — Description. — (Plates  XV-XVI1I.) — This  is  a  thin  irreg- 
ularly quadrilateral  muscle  situated  between  the  ribs  and  scapula  at  the  upper 
and  lateral  part  of  the  chest.  It  is  partly  covered  in  front  by  the  Pectoral 
muscles,  behind  by  the  Subscapulars.  The  axillary  vessels  and  nerves  lie 
upon  its  upper  part,  while  its  deep  surface  rests  upon  the  ribs  and  intercostal 
muscles. 

Origin.-  By  nine  digitations  or  slips  from  the  outer  surface  and  upper 
border  of  the  eight  upper  ribs  (the  second  rib  giving  origin  to  two  slips,)  and 
from  the  aponeurosis  covering  the  corresponding  intercostal  muscles.  The 
fiber-  pass  backward  closely  applying  the  chest  wall  and  the  vertebral  border  of 
the  scapula.  The  lower  four  slips  interdigitate  at  their  origin  with  the  upper 
five  slips  of  the  External  oblique  muscle  of  the  abdomen. 

Insertion.  — The  slips  from  the  first  and  the  higher  of  the  two  from  the 
second  rib.  converge  to  be  inserted  into  the  triangular  area  on  the  ventral 
aspect  of  the  superior  angle  of  the  scapula.  The  next  two  slips  spread  out  to 
form  a  thin  triangular  -heath,  the  base  of  which  is  directed  backward  and  is  in- 
serted into  nearly  the  whole  length  of  the  ventral  aspect  of  the  vertebral  border 
of  the  scapula.  The  lower  slips  converge  as  they  pass  backward  from  the  ribs 
and  form  a  fan-shaped  structure,  the  apex  of  which  is  inserted,  partly  by  mus- 
cular and  partly  by  tendinous  fibers,  into  the  triangular  impression  on  the  ven- 
tral  aspect    of   the  inferior  angle.     (Plate  XXI.) 

\<  tion. — A  pushing  muscle.     It  also  raises  the  point  of  the  shoulder. 

Xi:i;\  i.  SUPPLY.  Posterior  thoracic  which  is  derived  from  the  fifth,  sixth, 
and  seventh  cervical  nerves. 

Blood  Supply,     [ntercostals,  long  and  short  thoracic 


LESSON   XI. 

Levator  angull  scapulae. — Description.—  (1'late  XVIII.) — This  muscle  lies 
jusl  beneath  the  Trapezius  at  the  back  part  and  side  of  the  neck. 

Origin.  By  tendinous  -lips  from  the  transverse  process  of  the  atlas,  and 
from  the  posterior  tubercle-  of  the  transverse  processes  of  the  second,  third, 
and  fourth  cervical  vertebras.  These  slips  become  fleshy  and  unite  so  as  to 
form  a  flat   muscle  which  passes  downward  and  backward  to  its  insertion. 

Insertion.     Into  the  posterior  border  of  the  scapula  between  the  superior 


ANATOMY    IN    A    NUTSHELL.  55 

angle  and  the  triangular  smooth  surface  at  the  root  of  the  spine.     (Plate  XX.) 

Action. — To  raise  the  superior  angle  of  the  scapula. 

XeryeSupply. — Third  and  fourth  cervical,  and  frequently  by  a  branch  from 
the  nerve  to  the  Rhomboidei. 

Blood  Supply. — Vertebral,  ascending  cervical,  superficial  cervical,  and 
posterior  scapular. 

Rhomboideus  minor. — (Plate  XVIII.) — Origin. — Ligamentum  nucha1  and 
spinous  processes  of  the  seventh  cervical  and  first  dorsal  vertebrae. 

Insertion. — Smooth  surface  at  root  of  spine  of  scapula.       (Plate  XX.) 

Action. — To  draw  the  scapula  backward  and  upward. 

Nerve  Supply. — Fifth  cervical. 

Blood  Supply. — Posterior  scapular. 

Rhomboideus  major. — (Plate  XVIII.) — Description. — This  muscle  is 
situated  immediately  below  the  minor,  the  adjacent  margins  of  the  two  being 
occasionally  united. 

Origin. — Spinous  processes  of  the  four  or  five  upper  dorsal  vertebrae 
and  the  supra-spinous  ligament. 

Insertion. — Into  a  narrow  tendinous  arch  attached  above  to  the  lower 
part  of  the  triangular  surface  at  the  root  of  the  spine,  and  below  to  the  inferior 
angle,  the  arch  being  connected  to  the  border  of  the  scapula  by  a  thin  mem- 
brane. When  the  arch  extends  but  a  short  distance,  as  it  occasionally  does, 
the  muscular  fibers  are  inserted  into  the  scapula  itself.     (Plate  XX.) 

Action. — To  draw  scapula  backward  and  upward. 

Nerve  Supply. — The  fifth  cervical. 

Blood  Supply. — Posterior  scapular. 

Supraspinatus. — Description. —  (Plates  XXYIII-XY111.)  — The  supra- 
spinatus  muscle  occupies  the  whole  of  the  supraspinous  fossa.  The  fibers 
converge  to  a  tendon  which  pas>e>  across  the  upper  part  of  the  capsular  liga- 
ment of  the  shoulder  joint.. to  which  it  is  intimately  adherent. 

Origin. — (1)  Internal  two-thirds  of  supraspinous  fossa.  (2)  Strong 
fascia  covering  surface  of  fossa.     (Plate  XX.) 

Insertion. — Upper  facet  of  greater  tuberosity  of  humerus.    (Plate  XXIII.) 

A<  tion. — Raises  arm  and  supports  tuberosity  of  humerus. 

Xf.rve  Supply. — Fifth  and  sixth  cervical  through  the  suprascapular  nerve. 

Blood  Supply. — Suprascapular  artery. 

Infraspinatus. — Description. — (Plates  XXVII1-XVIII.)  This  is  a  thick, 
triangular  muscle  which  occupies  the  chief  part  of  the  infraspinous  fossa.  The 
fibers  converge  to  a  tendon  which  glides  over  the  external  border  of  the  spine 
of  the  scapula  and  passes  over  the  posterior  part  of  t  he  capsular  ligamenl  of  the 
shoulder-joint.  This  tendon  is  occasionally  separated  from  the  -pine  of  the 
scapula  by  a  synovial  bursa  which  communicates  with  the  synovial  cavity  of 
the  shoulder-joint. 

Origin. — (1)  Internal  two-thirds  of  infraspinous  fossa;  (2)  tendinous 
fibers  from  ridges  on  its  surface;  (3)  strong  fascia  covering  it  externally  ami 
separating  it  from  the  Teres  major  and  minor.      (Plate  \  \ 

Insertion.—  Middle  facet  of  greater  tuberosity  of  humerus.     (Plate  XXII.) 


56  ANAloMY    IX    A    NUTSHELL. 

A.ction.-  -Rotates  head  of  humerus  outward. 

Nerve  Slpply. — Fifth  and  Sixth  cervical  through  the  suprascapular  nerve. 

Blood  Supply.     Suprascapular  artery. 

Subscapulars.  Description. — The  subscapular  fascia  is  a  thin  mem- 
brane attached  to  the  entire  circu inference  of  the  subscapular  fossa,  and  afford- 
in--  attachment  by  its  inner  surface  to  some  of  the  fibers  of  the  Subscapularis 
muscle.  The  Subscapularis  is  a  large  triangular  muscle  which  fills  up  the  sub- 
scapular fossa.  The  muscle  terminates  in  a  tendon  which  is  in  close  contact 
with  the  anterior  part  of  the  capsular  Ligament  of  the  shoulder- joint  and  glides 
over  a  large  bursa,  which  separates  it  from  the  base  of  the  coracoid  process. 
This  bursa  communicates  with  the  cavity  of  the  joint  by  an  aperature  in  the 
capsular  ligament.  It-  anterior  surface  forms  a  considerable  part  of  the  pos- 
terior wall  of  the  axilla,  and  its  lower  border  is  contiguous  with  the  Teres  major 
and  Latissimus  dorsi  muscles. 

Origin. — (Plate  XXI.) — From  the  inner  two-thirds  of  the  subscapular 
fossa,  with  the  exception  of  a  narrow  margin  along  the  posterior  border,  and  the 
surface-  at  the  superior  and  inferior  angles;  also  from  the  lower  two-thirds  of 
the  groove  on  the  axillary  border  of  the  bone.  Some  fibers  arise  from  tendinous 
lamina',  which  intersect  the  muscle,  and  are  attached  to  ridges  on  the  bone, 
and  others  form  an  aponeurosis  which  separates  the  muscle  from  the  Teres 
major  and  the  long  head  of  the  Triceps. 

Insertion. — Lesser  tuberosity  of  the  humerus.     (Plate  XXIII.) 

A.CTION. — Rotates  head  of  humerus  inward. 

Nerve  Supply. — Upper  and  lower  subscapular  (first  and  third.) 

Blood  Supply.     Subscapular  artery. 

Teres  minor.— (Plates  XXVIII-XVIII.) — Description. — This  is  a  narrow, 
elongated  muscle  lying  between  the  Infraspinatus  and  Teres  major,  being  sep- 
arated from  the  latter  anteriority  by  the  long  head  of  the  Triceps. 

Origin.— Upper  two-thirds  of  dorsal  surface  of  axillary  border  of  the 
scapula  and  from  the  two  aponeurotic  laminae,  one  of  which  separates  it  from 
the  Infraspinatus,  the  other  from  the  Teres  major.     (Plate  XX.) 

Insertion.-  bower  facet  on  greater  tuberosity  of  humerus  and  bone  be- 
low.      (Plate  XXII.) 

A.CTION.     Rotates  head  of  humerus  outward. 

Xi:i;\i.Si  pply.— Fifth  cervical  through  the  circumflex. 

Blood  Supply.  -Infrascapular  from  dorsalis  scapulae,  circumflex  arteries. 

LESSON  XII. 

Teres  major.  Description.— (Plates  XXVIII-XVIII.)— This  is  a  thick, 
but  somewhat  flattened  muscle,  lying  immediately  below  the  Teres  minor.  Its 
fibers  are  directed  upward  and  outward  and  terminate  in  a  tendon  about  two 
inches  in  length.  This  tendon,  at  its  insertion,  lies  behind  that  of  the  Latissi- 
mus dorsi,  from  which  it  is  separated  by  a  synovial  bursa,  the  two  tendons, 
however,  being  united  along  their  borders  for  a  short  distance.  The  axillary 
vessels  and   the  brachial   plexus  of  nerves  lie  upon   its  anterior  surface.     Its 


PLATE  XVIII 


;Tsf SERRATUS      MAGNUS 


NTERNAL     OBLIQUE 


GREAT    SACRO- 
SCIATIC  LIG 


Muscles  of  Back  -Superficial   Layers 
57 


5S  ANATOMY    IN    A    NUTSHELL. 

lower  border  tonus,  in  conjunction  with  the  Latissimus  dorsi,  part  of  the  pos- 
terior  boundary  of  the  axilla. 

Origin.  From  the  oval  surface  on  the  dorsal  aspect  of  the  inferior  angle 
of  the  scapula,  and  from  the  fibrous  septa  interposed  between  it  and  the  Teres 
minor  and  Infraspinatus.     (Plate  XX.) 

Insertion,     [nner  bicipital  ridge  of  humerus.     (Plate  XXIII.) 

A.CTION.  Assists  Lattissimus  dorsi  in  drawing  humerus  downward  and 
backward. 

Nerve  Supply. — Fifth  and  sixth  cervical  through  the  lower  subscapular. 

Blood  Si  pply.     Subscapular  artery. 

Coraco-brachialis.  Description. — This  is  the  smallest  of  the  three  mus- 
cle- in  the  ant.  hum<  ral  region,  and  is  situated  at  the  upper  and  inner  part  of 
the  arm.  Its  fibers  pass  downward,  backward,  and  a  little  outward,  and  ter- 
minate in  a  Hat  tendon.  This  muscle  is  perforated  l>y  the  musculo-cutaneous 
nerve  and  its  inner  border  forms  a  guide  to  the  position  of  the  brachial  artery 
in  tying  this  vessel  in  the  upper  part  of  its  course.  The  brachial  vessels  and 
median  nerve  lie  upon  its  anterior  surface  at  its  insertion.      (Plate  XVI.) 

Origin.  Apex  of  coracoid  process  in  common  with  short  head  of  Biceps. 
(Plate  XX  1.) 

INSERTION.— Ridge  on  inner  side  of  shaft  of  humerus  about  its  middle, 
between  the  origins  of  the  Triceps  and  Brachialis  anticus.     (Plate  XXIII.) 

Action. — Draws  the  humerus  forward  and  inward  and  assits  in  elevating 
the  same. 

Nerve  Supply.— Seventh  cervical  through  the  Musculo-cutaneous. 

Blood  Supply. —  Brachial,  muscular  branches. 

Biceps. — Description. — (Plates  III-XY-XYI.) — The  Biceps  is  a  long 
fusiform  muscle,  occupying  the  whole  of  the  anterior  surface  of  the  arm,  and 
divided  above  into  two  portions  or  heads,  from  which  circumstance  it  has  re- 
ceived its  name.  Each  head  is  tendinous  but  is  succeeded  by  an  elongated 
muscular  belly,  and  the  two  bellies,  although  closely  applied  to  each  other, 
may  readily  be  separated  until  within  about  three  inches  of  the  elbow-joint. 
Here  they  end  in  a  flattened  tendon,  a  synovial  bursa  being  interposed  between 
it  and  the  front  of  the  tuberosity  of  the  radius.  As  this  tendon  approaches  the 
radius  it  become.-  twisted  U] itself  so  that  its  anterior  surface  becomes  ex- 
ternal. ( >pposite  the  bend  of  the  elbow  it  gives  off.  from  its  inner  side,  a  broad 
aponeurosis,  the  bicipital  fascia  (semilunar  fascia,)  which  passes  obliquely 
downward  and  is  continuous  with  the  deep  fascia  of  the  forearm.  The  Biceps 
muscle  occasionally  has  a  third  head  which  may  consist  of  two  slips  passing 
down,  one  in  front  of  the  other  behind  the  brachial  artery,  concealing  this  ves- 
sel in  the  lower  half  of  the  arm. 

The  inner  border  of  the  Biceps  froms  a  guide  to  the  position  of  the  artery 
in  tying  that  vessel  in  the  middle  of  the  arm. 

ORIGIN.— (Plates  XX-XXI.)  The  long  head  arises  from  the  upper  mar- 
gin of  the  glenoid  cavity  and  is  continuous  with  the  glenoid  ligament.  The 
tendon  arches  over  the  head  of  the  humerus,  being  enclosed  in  a  special  sheath 
of  synovial  membrane,  passes  through  an  opening  in  the  capsular  ligament  and 


ANATOMY    IX    A    NUTSHELL. 


59 


descends  in  the  bicipital  groove,  in  which  it  is  retained  by  a  fibrous  prolonga- 
tion from  the  tendon  of  the  Pectoralis  major. 

The  short  head  arises  from  the  apex  of  the  coracoid  process  in  common 
with  the  Coraco-brachialis. 

Insertion. — Back  of  tuberosity  of  radius;  fascia  of  forearm.     (Plate  XXV.) 

Action. — Flexes  and  supinates  forearm,  and  tenses  fascia. 

Nerve  Supply. — Fifth  and  sixth  cervical  through  the  musculo-cutaneous. 

Blood  Supply. — Brachial  artery,  muscular  branches. 

Omo-hyoid — Description. — This  muscle  passes  from  near  the  suprascapular 
notch  of  the  scapula  to  the  hyoid  bone,  thus  dividing  the  anterior  and  posterior 
triangles  of  the  neck  into  two  triangles  each.      (Plate  XIV.) 

Origin. — From  the  superior  border  of  the  scapula,  internal  to  the  supra- 
scapular notch.     (Plate  XX.) 

PLATE  XIX. 

MIDDLE    CONSTRICTOR     OF    PHARYNX. 
LESSER    CORNU. 

GREATER  CORNU 

\  f/  1/1      'If 

HYO-GLOSSUS. 

STYLO-  HYOID. 
THYRO-HYOID. 


GENIO-HYOID 


MYLO-HYOID 


STERNO-HYOID. 

The  Hyoid  Bone 


Insertion. — Into  the  lower  borderof  the  bgdy  of  hyoid  bone.   (Plate  XIX.) 

Blood  Supply. — Lingual  and  superior  thyroid  from  the  external  carotid, 
and  the  inferior  thyroid  from  the  thyroid  axis. 

Action. — Depresses  hyoid  bone. 

Nerve  Supply. — Branches  from  the  loop  betweenthe  cervical  plexus  and 
the  12th  cranial  nerve. 

Blood  Supply  of  Scapula. — The  glenoid  fossa,  supraspinous  fossa,  infra- 
Bpinous  fossa  and  the  spine  all  get  the  suprascapular  artery  from  the  thyroid 
axis.  The  infraspinous  fossa,  in  addition,  receives  the  dorsails  scapula?  which  is 
a  branch  of  the  subscapular,  from  the  third  portion  of  the  axillary.  1  he 
acromion  process  is  supplied  by  branches  from  the  arcomial  thoracic  artery.  The 
venter  receives  the  subscapular,  and  a  subscapular  branch  from  the  suprascapular; 
andthe  vertebral  border  receives  the  posterior  scapularfrom  the  suprascapular. 


60  ANATOMY    IN    A    NUTSHELL. 

LESSON  XIII. 

Humerus.-  (Plates  XXII-XXIII.) — The  humerus  is  the  longest  bone  in 
the  upper  extremity,  and  is  the  only  one  in  the  arm.  hs  upper  extremity  con- 
i  n  head,  neck  ami  two  tuberosities,  a  greater  ami  lesser.  The  head  is 
directed  inward,  upward  and  backward:  on  this  account  one  can  lift  his  arm 
higher  when  broughl  a  little  forward  than  when  at  right  angles  to  the  body;  the 
head  i-  about  a  hemisphere.  The  contracted  pari  below  the  head  is  called  the 
anatomical  neck;  it  is  rarely  broken,  while  the  part  below  the  tuberosity  is 
called  the  surgical  neck  on  accounl  of  it  being  the  seat  of  fracture.  Between 
the  two  neck-  are  the  tuberosities,  the  greater  on  the  outer  aspect  of  the  bone, 
separated  from  the  lesser  by  the  bicipital  groove  which  is  for  the  long  head  of 
the  Biceps. 

The  greater  tuberosity  has  three  facets,  the  upper  one  for  the  Supraspin- 
atus  muscle,  the  middle  one  tor  the  Infraspinatus  muscle,  and  the  lowerone  for 
the  Teres  minor.  The  lesser  tuberosity  is  in  the  form  of  a  cone  and  has  at- 
tached  to  it  the  Subscapulars.  The  bicipital  groove  extends  about  one-fourth 
the  way  down  the  bone;  its  outer  ridge  is  also  anterior  and  is  for  the  attach- 
menl  of  the  Pectoralis  major:  the  inner  ridge  is  posterior  and  is  for  the  attach- 
ment of  tin'  Too-  major;  the  groove  has  the  Latissimus  dorsi  attached.  The 
diaphysis  is  somewhat  triangular  on  cross  section  and  has  three  surfaces  and 
three  borders. 

The  anterior  border  extends  from  the  front  of  the  great  tuberosity  to  the 
coronoid  depression  below,  separating  the  external  from  the  internal  surface.-; 
it-  upper  part  is  the  external  bicipital  ridge  for  the  insertion  of  the  Pectoralis 
major  muscle;  the  lower  part  is  covered  by  the  Brachialis  anticus.  The  ex- 
ternal border  extends  from  the  posterior  part  of  the  great  tuberosity  to  the  ex- 
l  condyle,  and  separate-  the  external  and  posterior  surfaces;  its  lower  part 
i-  the  supracondylar  ridge.  From  above  downward  it  has  attached  the  lower 
pari  of  the  Teres  minor  on  the  posterior  aspect,  the  middle  or  long  humeral 
head  of  the  Tricep.-  separated  from  the  short  head  of  the  same  by  the  musculo- 
spiral  groove  which  transmits  the  musculo-spiral  nerve  and  the  superior  pro- 
funda artery.  The  external  supracondylar  ridge  has  attached  the  external 
intermuscular  septum  which  gives  attachment  to  five  muscles,  viz.,  Deltoid, 
Brachialis  anticus,  Triceps,  Supinator  longus,  and  Extensor  carpi  radialis 
longior.  The  internal  border  extends  from  the  inner  part  of  the  lesser  tuber- 
osity to  the  internal  condyle,  separating  the  internal  and  posterior  surfaces. 
From  above  downward  it  has  the  Teres  major,  and  Coraco-brachialis. 

|{el<>\\  the  Insertion  of  the  Coraco-brachialis  is  the  canal  for  the  nutrient 
artery,  which  run-  toward-  the  distal  extremity  of  the  bone  (Page  19,  Lesson 
3econd  canal  i-  often  presenl  on  the  posterior  surface;  its  artery  comes 
from  the  superior  profunda.  The  internal  intermuscular  septum  is  attached  to 
the  internal  supracondylar  ridge  and  has  attached  to  it  three  muscles,  viz., 
Tricep-.  Brachialis  anticus,  Coraco-brachialis,  and  occasionally  a  fourth  mus- 
cle. Pronator  radii  teres.  The  external  surface  gives  attachment  to  the  Del- 
toid about  two-fifth-  or  one-half  the  way  down  the  hone,  andbelow  this  to  the 


ANATOMY    IN    A    NUTSHELL.  61 

external  part  of  the  Brachialis  anticus.  The  internal  surface  gives  attachment 
to  the  Coraco-brachialis  opposite  the  Deltoid,  and  below  this  to  the  internal 
part  of  the  Brachialis  anticus. 

The  posterior  surface  has  the  two  lower  heads  of  the  Triceps  and  the  mus- 
culo-spiral  groove  separating  them.  The  lower  part  of  the  hone  articulates 
with  the  radius  and  ulna:  the  part  which  articulates  with  the  radius  is  called 
the  radial  head  or  capitellum  and  is  on  a  higher  level  than  the  part  which  artic- 
ulates with  the  ulna  which  is  called  the  trochlear  surface.  These  two  articula- 
ing  surfaces  are  separated  by  a  ridge.  Above  the  radial  head  on  the  external 
surface  is  the  radial  depression  for  the  head  of  the  radius  to  fit  into  when  the 
forearm  is  flexed;  above  the  trochlear  surface  on  the  internal  surface  is  the 
coronoid  depression  for  the  coronoid  process  of  the  ulna;  above  the  trochlear 
surface  on  the  posterior  surface  is  the  olecranon  depression  for  the  olecranon 
process  of  the  ulna. 

The  internal  condyle  is  more  prominent  than  the  external  one.  and  is  on 
a  lower  level.  It  gives  attachment  to  the  Pronator  radii  teres,  the  common 
tendon  for  some  of  the  flexors  of  the  forearm,  and  the  internal  lateral  ligament. 
The  external  condyle  is  less  prominent  than  the  internal  one  and  gives  attach- 
ment to  the  common  tendon  for  the  attachment  of  some  of  the  extensors  of  the 
forearm  as  well  as  the  Supinator  longus  and  external  lateral  ligament. 

Ossification. — The  ossification  is  from  seven  centers,  occasionally  eight. 
One  for  the  shaft  appears  about  the  eighth  week  of  intrauterine  life.  The  one 
for  the  head  the  first  year,  one  for  the  great  tuberosity  the  third  year;  occasion- 
al]}' one  for  the  lesser  tuberosity.  These  three  coalesce  at  the  17th  year  and  join 
the  shaft  about  the  20th  year.  At  the  distal  extremity  there  are  four  centers 
of  ossification;  one  for  the  capitellum  appears  at  the  3rd  year;  one  for  the  in- 
ternal condyle  at  the  5th  year;  one  for  the  trochlear  at  the  10th  year;  one  for 
the  external  condyle  at  the  14th  year. 

The  nucleus  of  the  internal  condyle  joins  the  shaft  in  the  18th  year,  while 
i  lie  other  three  nuclei  coalesce  and  join  the  shaft  the  17th  year. 

Articulation. — It  articulates  with  the  scapula,  radius,  and  ulna.  Its  artic- 
ulation with  the  scapula  makes  the  shoulder-joint,  a  description  of  which  is 
given  in  Lesson  IX;  and  its  articulation  with  the  radius  and  ulna  makes  the 
elbow-joint. 

Elbow-joint.— (Plates  XXXVIII-XXXIX.)— This  is  a  movable  joint  (dia- 
throsis)  and  belongs  to  the  sub-class  ginglymus  (hinge-joint.)  The  part  be- 
tween the  trochlear  surface  of  the  humerus  and  ihe  greal  sigmoid  cavity  of  the 
ulna  is  a  ginglymus  joint,  but  the  part  between  the  capitellum  of  the  humerus 
and  the  head  of  ihe  radius  is  an  arthrodial  join!  (gliding.)  The  pari  between 
the  lesser  cavity  of  the  ulna  ami  the  head  of  ihe  radius  is  a  trochoides.  The 
anterior  ligament  is  continuous  with  the  internal  and  external  lateral  ligaments 
covering  the  joint  in  froni  and  being  itself  covered  by  the  Brachialis  amicus; 
above,  it  is  attached  to  the  humerus  above  the  coronoid  and  radial  fossae  and 
in  front  of  the  internal  condyle;  below,  it  is  attached  to  the  anterior  surface  of 
the  coronoid  process  of  the  ulna  and  the  orbicular  ligamenl  and  the  neck  of  the 
radius. 


62  ANATOMY    IX    A    NUTSHELL. 

The  internal  lateral  ligament  is  continuous  with  the  anterior  and  posterior 
ligaments;  it  is  triangular  in  shape,  with  the  apex  above,  attached  to  the  in- 
ternal condyle  of  the  humerus;  the  anterior  angle  below  is  attached  to  the  inner 
edge  <>t'  the  coronoid  process.  Its  posterior  angle  below  is  attached  to  the  inner 
edge  of  the  olecranon  process.  There  are  filters  running  from  the  apex  to  eaeh 
inferior  angle,  also  fibers  connecting  the  inferior  angles.  The  Flexor  sublimits 
digitorum  is  attached  to  this  ligament. 

The  posterior  ligament  is  continuous  with  the  two  lateral  ligaments;  it 
is  attached  above  to  the  margin  of  the  olecranon  fossa  and  below  to  the  ole- 
cranon process  ami  orbicular  ligament. 

The  external  lateral  ligament  is  attached  above  to  the  depression  below  the 
external  condyle  of  the  humerus;  below,  it  is  attached  to  the  orbicular  liga- 
ment, head  of  the  radius  and  the  outer  side  of  the  ulna:  there  are  two  muscles 
attached  to  this  ligament,  the  Extensor  carpi  radialis  brevior  and  Supinator 
brevis.  These  four  ligaments  make  a  capsular  ligament.  Synovial  mem- 
brane lines  that  portion  of  the  ligaments  and  bones  which  make  the  joint  and 
sends  a  part  into  the  superior  radio-ulnar  articulation. 

The  ligamentous  muscles  of  the  elbow-joint  are  the  Biceps,  Triceps.  Bra- 
chials anticus  and  all  the  muscles  in  the  forearm  except,  the  Flexor  profundus 
digitorum,  Flexor  longus  pollicis.  Pronator  quadratus  and  Extensor  ossis  met- 
acarpi  pollicis.  Extensor  brevis  pollicis.  Extensor  longus  pollicis  and  Extensor 
indicis. 

Nerve  supply.— Musculo-spiral,  musculo-cutaneous,  median  and  ulnar 
nerve-. 

Blood  supply. — Anterior  and  posterior  ulnar  recurrent,  radial  recurrent. 
interosseous  recurrent,  anastomatica  magna,  superior  profunda  and  inferior 
profunda. 


LESSON   XIV. 

ARTERIES. 

Axillary  artery.  The  subclavian  artery  passes  under  the  clavicle  and  over 
the  firsl  rib,  from  the  lower  surface  of  which  it  is  called  the  Axillary  artery  until 
it  leaves  the  axillary  space  at  the  lower  border  of  the  tendon  of  the  Teres  major, 
then  it  take.-  the  name  Brachial  artery.  This  artery  is  crossed  by  the  Pector- 
alis  minor  muscle  which  divides  the  artery  into  three  (tarts;  the  pari  above  it  is 
called  the  firsl  pari,  the  part  behind  it  is  called  the  second  part  ami  the  part 
below  it  is  called  the  third  part  (Plate  XVI.) 

Branches.  This  artery  has  seven  branches,  (Plate  XVII)  two  from  the 
first  portion,  the  superior  thoracic  and  the  acromial  thoracic;  two  from  the  sec- 
ond portion,  the  alar  thoracic  ami  the  long  thoracic  or  external  mammary,  and 
three  from  the  third  portion,  the  subscapular,  anterior  circumflex,  and  poster- 
ior circumflex. 

The  superior  thoracic  arises  so  close  to  the  upper  border  of  the  axillary 
artery  that  it  is  sometimes  given  as  a  branch  of  the  subclavian.  It  may  come 
from  the  acromial  thoracic  axis.      It  i>  between  the  Pectoralis  major  and  minor. 


ANATOMY    IN    A    NUTSHELL. 


63 


along  the  upper  border  of  the  latter,  supplying  both  these  muscles,  the  Ser- 
ratus  magnus  and  the  chest  wall.  It  anastomoses  with  the  internal  mammary, 
intercostal  arteries  and  the  long  thoracic.  It  helps  to  supply  the  sterno-clav- 
icnlar  joint. 

The  acromial  thoracic  arises  just  above  the  Pectoralis  minor  from  the  front 


CORACO-ACROMIAl   LIG'T. 


PLATE  XX 

0M0-HY0  D  AND  TRANSVERSE 
LIGAMENT.(O) 


SUP.  ANGLE. 


LEVATOR  ANGUU 
SCAPULAE.  (I) 

SUPRASPINATUS(O). 


Q 
NECK 

NOTCH 

GLENOID  FOSSA  AND  HEAD 

CAPSULAR  LIGAMENT. 

GROOVE  FOR  DORSAL 
ARTERY  OF  THE  SCAPULA. 

TERES  MINOR.(O) 


RHOMBOIDEUS 
MAJOR.(I). 


TERES  MAJOR.(O) 


lattissimus  dorsi.(o)  — ^^t^j^'  inf.  angle. 

The  Left  Scapula  —  Posterior  Surface,  or   Dorsum 

pari  of  the  artery.  It  has  an  axis  and  gives  off  three  branches.  (1)  humeral 
or  descending  branch  which  passes  down  bet  ween  the  Pectoralis  major  and 
Deltoid  with  the  cephalic  vein,  supplying  both  these  muscles;  it  anastomoses 
with  the  anterior  and  posterior  circumflex  arteries.  (2)  the  acromial  branch 
which  supplies  the  Deltoid  muscle  and  the  acromio-clavicular  joint,  anastom- 
osing  with    the   anterior  and    posterior   circumflex    and   suprascapular   arteries 


1.1 


ANATOMY    IX    A    NUTSHELL. 


making  the  acromial  rete.  [f  we  substitute  in  this  rete  or  net-work  of  arter- 
ies, thisbranch  for  the  subscapular  artery  we  will  have  the  blood  supply  to  the 
shoulder-joint.  (3)  The  thoracic  branches  supply  the  Pectoral  muscles  and  the 
Serratus  magnus,  and  anastomoses  with  the  intercostal  arteries  both  from  the 
aorta  and  the  internal  mammary.  There  are  two  or  three  of  these  branches. 
I     \  clavicular  branch  may  pass  to  the  Subclavius  muscle. 

PLATE  XX] 

CONOID  LIG'T.     TRAPEZOID   LIGT     BICEPS  AND  CORACOBRACHIALIS 


RIOCES 


SERRATUS 
MAGNUS. 


Tin    I.i  l  i   Si  \n  i.\     Anterior  Surface,  or  Venter 


The  alar  thoracic  is  no1  a  constanl  branch;  ii  supplies  the  glands  and  half 
of  the  axillary  space.  V>  hen  ii  is  absenl  its  place  is  filled  by  a  branch  from  on.' 
of  the  other  thoracic  arteries. 

The  anterior  or  ion-  thoracic,  oi  external  mammary  passes  along  the  lower 
border  of  the  Pectoralis  minor  muscle  to  about  the  sixth  intercostal  space,  sup- 
plying the  Pectoral  and  Serratus  magnus  muscles,  and  the  mammary  gland. 
h  anastomoses  with  the  intercostal,  internal  mammary,  and  superior  thoracic 


ANATOMY    IN    A    NUTSHELL.  65 

arteries.     There  is  often  an  accessory  external  mammary  which  is  behind  the 
main  branch. 

The  anterior  circumflex  arises  from  the  outer  side  of  the  axillary  artery, 
passing  between  the  Coraco-brachialis  and  the  short  head  of  the  Biceps  around 
the  anatomical  neck  of  the  humerus  to  the  under  surf  ace  of  the  Deltoid,  which 
it  supplies.  A  branch  from  this  artery  passes  up  the  bicipital  groove,  with  the 
longhead  of  the  Biceps,  to  supply  the  shoulder-joint;,  [ts anastomoses  with  the 
posterior  circumflex  and  acromial  thoracic.  An  occasional  cut  mucous  branch 
is  often  given  to  the  floor  of  the  axilla. 

The  posterior  circumflex  comes  from  the  posterior  part  of  the  artery,  below 
the  subscapular.  It  passes  through  the  quadrilateral  space  which  is  bounded 
above  by  the  Teres  minor,  below  by  the  Teres  major,  on  the  inner  side  by  the 
long  head  of  the  Triceps  and  on  the  other  side  by  the  humerus;  its  veins  and 
the  circumflex  nerve  go  with  it.  It  anastomoses  with  the  anterior  circumflex, 
subscapular,  suprascapular,  acromial  thoracic,  and  a  branch  from  the  superior 
profunda.  This  artery  maybe  a  branch  from  the  brachial,  superior  profunda, 
or  may  come  from  a  common  trunk  with  the  subscapular.  It  goes  to  the  Del- 
toid, long  head  of  the  Triceps,  Teres  minor,  shoulder-joint  and  head  of  the 
humerus. 

The  subscapular  artery  runs  along  the  lower  border  of  the  Subscapularis 
muscle  with  the  subscapular  nerve  to  the  inferior  angle  of  the  scapula,  where  it 
anastomoses  with  the  posterior  scapular  and  a  terminal  branch  of  the  trans- 
versalis  colli;  it  also  anatomoses  with  the  intercostal  and  long  thoracic  arter- 
ies. It  gives  branches  to  the  glands  and  areolar  tissue  of  the  axilla,  to  the 
Teres  major,  Latissimus  dorsi.  Subscapular  which  passes  through  the  triangu- 
lar space  bounded  above  and  internally  by  the  Subscapularis,  below  by  the 
Teres  major,  and  externally  by  the  long  head  of  the  Triceps.  It  anastomoses 
with  the  suprascapular  and  posterior  scapular  arteries.  It  gives  branches  to 
the  Subscapularis  and  Infraspinatus  muscles. 

Relations. — First  Portion  of  Axillary  Artery. 

In  Front. — (1)  Pectoralis  major,  (2)  Costo-coracoid  membrane,  (3)  Ex- 
ternal anterior  thoracic  nerve,  (4)  Acromio-thoracic  vein,  (5)  Cephalic  vein. 

Behind. — (1)  First  intercostal  space,  (2)  First  intercostal  muscle,  (3) 
Second  and  third  serrations  of  Serratus  magnus.  (4)  Posterior  thoracic  nerve, 
and  (5)   Internal  anterior  thoracic  nerve. 

Outer   Side. — Brachial    plexus. 

[nnee  Side. — Axillary  vein. 

Second  Portion  of  Axillary  Artery. 

Ix  Front. — (1)  Pectoralis  major.  (2)   Pectoralis  minor. 

BEHIND. — (1)   Subscapularis,    (2)    Posterior  cord   of   plexus. 

Outer  Side.     Outer  cord  of  plexus. 

Ixwkk  Side.— (1)  Axillary  vein,  (2)  Inner  cord  of  plexus,  and  (3)  Inter- 
nal anterior  thoracic  nerve. 

Third  Portion  of  Axillary  Artery. 

Ix  Front. — (1)  Integument  and  fascia.  (2)  Pectoralis  major,  (•">")  Inner 
head  of  median  nerve,  and  (4)   Internal  cutaneous  nerve. 


66  ANATOMY    IN    A    NUTSHELL 

Behind. — (1)  Subscapular^,  (2)  Tendon  of  Latissimus  dorsi,  (3)  Tendon 
of  Teres  major,  (4;  Musculo-spiral  nerve,  and  (5)   Circumflex  nerve. 

Outer  Side.— (1)  Coraco-brachialis,  (2)  Median  nerve.  (3)  Musculo- 
cutaneous nerve. 

Inner  Side.— (1)  Tina  nerve.  (2)  Lesser  internal  cutaneous  nerve,  and 
(3)  Axillary  veins. 


LESSON   XV. 

Brachial  artery. — Plato  XYI-XYII.) — The  brachial  artery  extend-  from 
the  lower  border  of  the  Teres  major,  above  which  it  is  called  Axillary,  to  about 
one  and  a  half  inches  below  the  elbow  where  it  divides  into  the  Radial  and 
Ulnar.  It  passes  along  the  inner  and  fore  part  of  the  arm.  being  accompanied 
by  venae  comites  and  is  comparatively  superficial.  It  has  the  following  rela- 
tions: 

1\  Front. — (1)  Integument  and  fascia.  (2)  Bicipital  fascia.  (3)  Median 
basilic  vein,  (4)  Median  nerve,  and  (5)  Overlapped  by  Coraco-brachialis  and 
Biceps. 

Behind. —  (1)  Triceps,  (2)  Musculo-spiral  nerve.  (3)  Superior  profunda 
artery,  (4)  Coraco-brachialis  (insertion),  and  (5)  Brachialis  anticus. 

Outer  Side. — (1)  Vena  comes.  (2)  Median  nerve  (above),  (3)  Coraco- 
brachial'^, and  (4)   Biceps. 

[nner  Side. — (1)  Vena  come-.  (2)  Internal  cutaneous  nerve.  (3)  Ulnar 
nerve,  I  b    Median  nerve  (below),  and  (5)  Basilic  vein  (upper  half). 

[ts  branches  are  the  superior  profunda,  inferior  profunda,  nutrient,  mus- 
cular, anastomotica  magna,  and  occasionally  the  vasa  aberrantia. 

The  superior  profunda,  the  largest  branch,  arises  from  the  inner  and  back 
pari  of  the  artery  opposite  the  lower  border  of  the  Teres  major.  It  winds  back- 
ward and  outward  with  the  musculo-spiral  nerve  in  the  musculo-spiral  groove. 
It  gives  off  an  anterior  branch  which  pierces  the  external  intermuscular  septum 
to  anastomose  with  the  radial  recurrent.  It  continues  behind  the  external 
intermuscular  septum  with  a  branch  of  the  musculo-spiral  nerve  to  the  An- 
coneus, where  it  anastomoses  with  the  anastomotica  magna  and  interosseous  re- 
current. It  supplies  the  Triceps  and  Anconeus.  The  anterior  branch  which 
it  gives  off  passes  to  the  front  of  the  elbow  in  the  groove  between  the  Supinator 
longus  ami  the  Brachialis  amicus  to  the  front  of  the  external  condyle.  It  gives 
branches  to  the  Deltoid,  Brachialis  anticus,  and  Triceps,  and  a  branch  to  anas- 
tomose with  the  circumflex  artery.  The  artery  continues  as  the  posterior 
branch. 

The  inferior  profunda  may  come  from  the  superior  profunda,  but  generally 
comes  from  the  brachial  opposite  the  insertion  of  the  Coraco-brachialis.  It 
accompanies  the  ulnar  nerve  to  the  back  of  the  internal  condyle,  having  pierced 
the  internal  intermuscular  septum  from  before  backward.  It  anastomoses  with 
tin-  anastomotica  magna  ami  posterior  ulnar  recurrent.  lt>  anterior  branch 
extends  to  the  front  of  the  internal  condyle  to  anastomose  with  the  anastomo- 
tica magna  and  anterior  ulnar  recurrent. 


PLATE  XXII. 


CAPSULAR  LIGAMENT 
INFRASPINATUS  (I). 

TERES  MINOR  (I) 


(RICEPS  (EXT.  HEAO)  (0) 


MUSCULO-SPIRAL  GROOVE 


ANCONEUS  (0). 
EXTERNAL  CONDYLE. 
EXT.  LATERAL  LIGAMENT 


TRICEPS  (INT.  HEAD).(OJ. 


.HEAO. 


CAPSULAR  LIGAMENT. 
OLECRANON  FOSSA. 


-FLEXOR  CARPI  ULNARIS  (0) 


INT.  CONDYLE. 


GROOVE  FOR  ULNAR  NERVE. 


The  Left  Bumerus — Posterior  \  uw 
67 


PLATE  XXIII. 


HEAD.  

SUBSCAPULAR  (I) 
CAPSULAR  LIGAMENT 
LESSER  TUBEROSITY.*!.) 
LATISSIMUSDORSI 

TERES  MAJOR  (I) 


CORACOBRACHIAL^  (I) 


IBRACHIALIS  ANTICUS  (I) 


NUTRIENT  FORAMEN 


fSUPRACONDYLOID    PROC 


PRONATOR  RADII  TERES  (0). 
FLEXOR  CARPI  RADIALIS  (0) 
PALMARIS  LONGUS  (0) 
FLEXOR  SUBLIMIS  DIGITORUM  (0) 
rLEXOR  CARPI  UNARIS  (01 
INT.  CONDYLE. 
INT.  LATERAL  LIGAMENT 

CAPSULAR  LIGAMENT 


SUPRASPINOUS  (I). 

GREATER  TUBEROSITY. 

TRANSVERSE  HUMERAL  LIGAMENT. 


BICIPITAL  UI.OOVE. 
PECTORALIS  MAJOR  (I). 


ROUGH  SURFACE  FOR  DELTOID. 


SUPINATOR  LONGUS.  (0). 

EXT.  CONDYLAR  RIOGE 
EXTENSOR  CARPI  RADIALIS  LONGIOR  (0) 
CORONOiD  rossA 
RADIAL  DEPRFSSION 
EXTtNSOR  CARPI  RADIALIS  BREVIOR  (0). 
EXTENSOR  COMMUNIS  DIGITORUM  (U) 
EXTENSOR  MINIMI  OlGlTI  (0). 
EXTENSOR  CARPI  ULNARIS  (0). 
SUPINATOR  8REVIS  (0) 
EXTERNAL  CONDYLE. 
EXT.  LAItHAL  LIGAMENT. 


The     Left  Hi  merus     Anterior  View 
68 


ANATOMY    IN    A    NUTSHELL.  69 

The  nutrient  artery  comes  from  the  brachial  about  the  middle  of  the  fore- 
arm; it  pierces  the  tendon  of  the  Coraco-brachialis  to  enter  the  nutrient  canal 
which  is  below  the  insertion  of  the  Coraco-brachialis;  It  is  directed  towards 
the  elbow  (page  19.  Lesson  1.)  A  branch  from  the  musculo-cutaneous 
nerve  enters  the  bone  with  this  artery.  The  artery  may  be  a  branch  of  the 
superior  profunda. 

The  muscular  branches  are  three  or  four  in  number  and  arise  from  the  outer 
>ide  of  the  artery  and  supply  the  Bicep-.  Coraco-brachialis,  and  Brachialis 
amicus.     The  same  muscles  are  supplied  by  the  musculo-cutaneous  nerve. 

The  anastomotica  magna  arises  two  inches  above  the  elbow-joint,  passing 
inward  over  the  Brachialis  anticus  to  pierce  the  internal  intermuscular  septum 
to  pass  to  the  back  of  the  internal  and  external  condyles.  It  anastomoses  in 
front  of  the  internal  condyle  with  a  branch  from  the  inferior  profunda  and  an- 
terior ulnar  recurrent.  It  anastomoses  behind  the  internal  condyle  with  the 
sterior  branch  of  the  inferior  profunda  and  the  posterior  ulnar  recurrent. 
It  anastomoses  behind  the  external  condyle  with  the  posterior  branch  of  the 
superior  profunda  and  the  interosseous  recurrent. 

The  vasa  aberrantia  are  collateral  branches  which  connect  the  brachial 
or  axillary  artery  with  the  arteries  of  the  forearm,  generally  with  the  radial. 

Forearm. — There  are  twenty  muscles  in  the  forearm,  eight  in  the  anterior 
(radio-ulnar)  region  arranged  in  four  layers:  in  the  first  layer  there  are  four — 
I  Plate  XXIX) — The  Pronator  radii  teres.  Flexor  carpi  radialis,  Palmaris  longus, 
and  Flexor  carpi  ulnaris.  The  first  three  of  these  are  supplied  by  the  median 
nerve,  which  conies  from  the  outer  and  inner  cords  of  the  brachial  plexus.  The 
Flexor  carpi  ulnaris  is  supplied  by  the  ulnar  nerve,  which  comes  from  the  inner 
cord.  (Plate  VI.)  In  the  second  layer  there  is  one  muscle,  the  Flexor  sublimis 
digitorum.  (Plate  XXX.)  It  is  supplied  by  the  median  nerve.  In  the  third 
layer  there  are  two  muscles.  (Plate  XXXI.)  Flexor  longus  pollicis  and  the  Flexor 
profundus  digitorum.  The  first  is  supplied  by  the  anterior  interosseous,,  which 
is  a  branch  of  the  median;  the  second  one  by  the  anterior  interosseous  and  the 
ulnar.  In  the  fourth  layer  there  is  one  muscle,  the  Pronator  quadratus,  which 
is  supplied  by  the  anterior  interosseous  nerve. 

In  the  radial  region  there  are  threemuscles  (Plate  XXXII)  Brachio-radialis 
(Supinator  longus,)  Extensor  carpi  radialis  longior,  and  the  Extensor  carpi 
radialis  brevior.  The  first  two  are  supplied  by  the  musculo-spiral  nerve:  the 
last  one  by  theposterior  interosseous  aervewhich  Lsa  branch  of  the  musculo- 
spiral  nerve. 

In  the  posterior  radio-ulnar  region  there  are  nine  muscles,  Plate  XXXII,) 
four  in  the  superficial  layer  andfive  in  the  deep  layer.  Thefour  in  the  superficial 
layer  are  the  Extensor  communis  digitorum,  Extensor  minimi  digiti,  Extensor 
carpi  ulnaris,  and  Anconeus.  The  fust  three  are  supplied  by  the  posterior  in- 
terosseous nerve;  theAnconeus  by  the  musculo-spiral  nerve.  (Plate  XXXIII). 
The  five  muscles  in  the  deep  layer  are  the  Supinator  brevis,  Extensor  ossis  meta- 
carpi  pollicis.  Extensor  brevis  pollicis.  Extensor  longus  pollicis,  and  the  Exten- 
sor  indicis;  they  are  all  supplied  by  the  posterior  interosseous  nerve. 

The  bones  of  the  forearm  are  the  radius  and  ulna:  the  radius  has  nine  mus- 


PLATE  XXIV 


GROOVES  FOR  -  1ST.-  EXTENSOR  OSSIS  METACARPI  POLLICIS  AND  EXTENSOR  PRIMI  INTERNODII  POLLICIS. 
2ND. -EXTENSOR  CARPI  RADIALIS  LONGIOR  AND  BREVIOR. 
3RD.  -    EXTENSOR  SECUNDI  INTERNODII  POLLICIS 

4TH.-EXTENS0R  COMMUNIS  DIGITORUM  AND  EXTENSOR  INDICIS. 
5TH.-EXTENS0R  MINIMI  DIGITI. 

6  TH.- EXTENSOR  CARPI  ULNARIS. 


POSTERIOR  RADIO-ULNAR  LIGAMENT 


IAL   LATERAL  LIGAMENT 


—  POSTERIOR  RADIO-CARPAL  LIGAMENT. 


TRICEPS  (I) 


SUPINATOR  BREVIS  (I). 


BICEPS  (I). 


LOWER  LIMIT  OF  ORBICULAR  LIGAMENT; 


CAPSULAR  LIGAMENT. 


I.i  ii    Radius  and  Ulna— Posterior  View. 

70 


PLATE  XXV. 


INTER- ARTieULAft-FIBHO-CARTIUCE. 

ANTERIOR  RADIO-CARPAL  LIGAMENT. 
IlXT.  LATERAL  LIGAMENT 


SUPINATOR  LONGUS.lll 


PRONATOR  QUAORATUS  (I). 


FLEXOR  LONGUS  POLLICIS.(O), — 
RADIUS 

PRONAIOR  RADII  TERES/1) 

FLEXOR  SUBLIMISDIGITORUM.    (0 
OBLIQUE  LINE. 


SUPINATOR 

BICIPITAL  TUBERCLE 

BICEPS.  (I)"" 

LOWER  LIMIT  OF  ORBICULAR  LIGAMENT 

NECK  OF  RADIUS 
HEAD  OF  RADIUS 


GREATER  SIGMOID  FOSSA. 


INT    LATERAL  LIGAMENT 
ANT.  RADIO-ULNAR  LIGAMEN 


PRONATOR  QUADRATUS. 'O 


INTEROSSEOUS  MEMBRANl. 


FLEXOR  PROFUNDUS  DIGITORUM.iO ■ 


NUTRIENT  FORAMEN. 


OBLIQUE  LIGAMENT 

FLEXOR  LONGUS  POLLlClS(O) 
~  (ACCESSORY  HEAD). 
BRACHIALIS  ANTICUS. 
PRONATOR  RADII  TERESILESSER  HEAD)(0) 

TUBERCLE  FOR  FLEXOR  SUBLIMIS 
DIGITORUM. 

INT.  LATERAL  LIGAMENT 
CAPSULAR  LIGAMENT 


Left  Radius  and  Ulna— Anterior  View. 

71 


72  ANATOMY    IN"    A    NUTSHELL. 

cles  attached  to  it  and  the  ulna  fourteen.  Although  there  are  twenty-three 
muscles  attached  to  these  two  bones,  yet  there  are  but  twenty  muscles  in  the 
forearm,  the  Triceps,  Biceps,  and  Brachialis  anticus  are  in  the  arm  (between 
the  shoulder  and  elbow.)     The  elbow-joint  isdescribed  in  Lesson  XIII. 

LESSON  XVI. 

The  Radius  (Plates XX IV-XXV)  is  theshorterof  thetwo bones  of  the  fore- 
arm. Its  distal  extremity  is  larger  than  that  of  the  ulna,  while  its  proximal  extrem- 
ity is  smaller  than  that  of  the  ulna.  Thesetwo  boneslie  parallel.  The  proximal 
extremity  has  a  head,  neck,  and  tuberosity;  the  circumference  of  the  head  is 
concave,  tts  inner  portion  which  articulates  with  the  lesser  sigmoid  cavity  of 
the  ulna  is  broader  than  the  remaining  portion  which  articulates  in  the  orbicu- 
lar Ligament.  The  upper  surface  of  the  head  is  also  concave  for  the  articula- 
tion of  the  capatellum  or  radial  head  of  the  humerus;  it  is  covered  with  cartil- 
age in  the  recent  state.  The  neck  is  the  constricted  part  below  the  head;  the 
proximal  part  of  the  neck  is  surrounded  by  the  distal  part  of  the  orbicular  lig- 
ament and  distally  it  gives  attachment  to  the  Supinator  brevis  externally.  The 
bicipital  tuberosity  is  distally  from  the  neck  at  the  antero-internal  aspect  of  the 
bone.  It  has  a  rough  posterior  portion  for  the  insertion  of  the  tendon  of  the 
Biceps,  and  a  smooth  anterior  portion  for  a  bursa  which  is  between  the  tendon 
and  the  bone.  The  shaft  is  triangular  on  cross  section  and  has  three  borders 
and  three  surfaces.  The  anterior  border  extends  from  the  bicipital  tuberosity 
distally  to  the  outer  aspect  of  the  bone,  then  to  the  anterior  border  of  the  sty- 
loid process.  The  proximal  one-third  of  this  border  is  the  oblique  line  of  the 
radius;  it  separates  the  Supinator  brevis  from  the  Flexor  longus  pollicis,  and 
gives  a1  tachmenl  to  the  third  head  of  the  Flexor  sublimis  digitorum ;  it  separates 
the  anterior  surface  from  theexternal  surface.  The  inner  or  interosseous  bor- 
der, extends  from  the  posterior  pail  of  the  bicipital  tuberosity  proximally  to 
the  sigmoid  cavity  of  the  radius;  its  distal  part  divides  into  an  anterior  and 
posterior  portion  and  has  the  interosseous  membrane  attached  to  most  of  its 
extent;  it  separates  the  anterior  from  the  posterior  surface.  The  posterior 
border  which  is  well  marked  in  the  middle  one-third,  extends  from  the  back 
pari  of  the  neck  of  the  radius  to  the  middle  tubercle  on  the  posterior  aspect  of 
the  distal  extremity;  it  separates  the  posterior  from  the  external  surface.  The 
anterior  surface  is  concave  at  the  proximal  extremity  and  smooth  at  the  distal 
extremity. 

The  proximal  three-fourth  gives  attachment  to  the  Flexor  longus  pollicis, 
and  the  distal  one-fourth  to  the  Pronator  quadratus.  Where  the  proximal  one- 
third  joins  the  middle  one-third,  is  the  nutrient  foramen  which  is  directed  to- 
wards  the  elbow.  The  nutrient  artery  is  a  branch  of  the  anterior  interosseous. 
'I'h.  posterior  surface  is  convex  from  the  proximal  to  the  distal  extremity;  it 
is  covered  by  the  Supinator  brevis.  Extensor  ossis  metacarpi  pollicis,  Extensor 
brevis  pollicis.  and  the  distal  one-third  is  covered  by  tendons.  The  oblique  line 
marks  the  proximal  limit  of  the  Extensor  ossis  metacarpi  pollicis.     The  exter- 


ANATOMY    IN    A    NUTSHELL. 


73 


nal  surface  is  convex  from  the  proximal  to  the  distal  extremity;  it  has  attached 
to  it  the  Supinator  brevis,  and  about  the  center  the  Pronator  radii  teres,  and 
distally  it  is  covered  by  the  Extensor  carpi  radialis  longior  and  Extensor  carpi 
radialis  brevior  which  are  crossed  by  the  Extensor  ossis  metacarpi  pollicis  and 
Extensor  brevis  pollicis. 

The  lower  extremity  is  quadilateral.     The  lower  surface  which  is  concave, 
articulates  with  the  scaphoid  and  semilunar.     The  part  which  articulates  with 

PLATE  XXVI 

EXTENSOR   COMMUNIS   DIGITORUM    (I) 


EXTENSOR 

MINIMI  DIGITI  (I), 


(I)  EXTENSOR  INOICIS. 


EXTENSOR 
SECUNDI  INTFRNODII 
POLLICIS. 


EXTENSOR 
CARPI  UL:.ARIS.     (I)  — r\ 


PISIFROM 


il)  EXTENSOR 
PRIMI  INTERNOOII 
POLLICIS. 

1ST  METACARPUS. 


EXTENSOR  CARPI 
RADIALIS  LONGIOR 
AND  BREVIOR. 


Bones  of  Left  Hand— Posterior  View 


the  scaphoid  is  triangular,  while  that  which  articulates  with  the  semilunar  is 
quadrilateral.  These  part- are  separated  by  a  ridge.  The  inner  surface  is  concave 
and  articulates  with  the  head  of  the  ulna.  The  interarticular  fibro-cartilage 
is  attached  to  the  border  between  the  sigmoid  cavity  and  the  semilunar  sur- 
faces. 

The  perimeter  is  triangular,  having  an   anterior,  external,  and   posterior 


74 


ANATOMY    IN    A     NUTSHELL. 


surfaces.  The  anterior  surface  gives  attachment  to  the  anterior  ligament  of 
the  wrist,  the  external  is  prolonged  downward  making  the  styloid  process  to 
the  base  of  which  is  attached  the  Supinator  longus  and  to  the  apex  externally 
the  lateral  ligament.  This  process  has  a  groove  passing  distally  and  forward  for 
the  Extensor  ossis  metacarpi  pollicis  and  Extensor  brevis  pollicis.  The  poste- 
rior surface  gives  attachment  to  the  posterior  ligament  and  has  three  grooves* 
which  are  lir>t.  for  the  Extensor  carpi  radialis  lorigior  and  brevior,  the  second 
for  the  Extensor  longus  pollicis.  and  the  third  for  the  Extensor  communis 
digitorum  ami  Extensor  indicis. 

PLATE  XXVII 


(I)     FLEXOR  PROFUNDUS  DIGITORUM. 


(I)    FLEXOR 
SUBLIMUS  DIGITORUM 


I1'  FLEXOR  LONGUS 
POLLICIS 


(I)     FLEXOR  BREVIS  ANO 
ADDUCTOR  POLLICIS. 
A30UCTOR  POLLICIS.  ANt 
(I)    FLEXOR  BREVIS 


OPPONENS  POLLICIS 
Ml     FLEXOR  CARPI  RADIALIS. 

HI      EXTENSOR 

OSSIS  METACARPI  POLLICIS 


(0)     OPPONENS  POLLICIS 

ABDUCTOR  POLLICIS.  (0) 


(I)  ABDUCTOR  AND 

FLEXOR  BREVIS  MINIMI  DIGIT! 


(I)     OPPONENS  MINIMI  DIGITI. 
(0)    ABDUCTOR  TRANSVERSUS  POLUCIS. 


(I)     FLEXOR  CARPI  ULNARIS. 


OPPONENS  MINIMI  DIGITI     (0.) 
FLEXOR  BREVIS  MINIMI  DIGITI  (0)." 


(0)    ABDUCTOR   MINIMI  DIGTI 
(I)    FLEXOR  CARPI   ULNARIS. 


FLEXOR  BREVIS    POLLICIS.    (0) 

(0)     ADDUCTOR    0BLIQUUS    POLLICIS. 

Bones  oi    Left  Hand-   Anterior  View 

Ossification.     From    three   centers,   one   for   the   diaphysis   about    the 

eighth  week  of  intrauterine  life,  one  for  the  distal  epiphysis  about  the  second 

year  which  join-  the  bone  aboul  the  twentieth  year,  and  one  for  the  proximal 

extremity,  the  fifth  year,  which  joins  the  bone  about  the  seventeenth  year. 

grooves  correspond    to  the  second,  third,  and  fourth  of   the  posterior  annular  ligament 
oi  tin-  wrist-joint 


ANATOMY    IN    A    NUTSHELL.  75 

Articulation.  —  It  articulates  with  four  bones,  the  humerus,  ulna,  scap- 
hoid  and  semilunar. 

Muscles. — It  has  nine  muscles  attached,  the  Biceps,  third  head  of  the 
Flexor  sublimis  digitorum.  Supinator  brevis,  Flexor  longus  pollicis,  Pronator 
quadratus,  Pronator  radii  teres.  Supinator  longus,  Extensor  ossis  metacarpi 
pollicis  and  Extensor  brevis  pollicis. 

Blood  Supply. — The  nutrient  artery  is  derived  from  the  anterior  inter- 
osseous trunk:  it  enters  the  shaft  near  the  middle  of  the  anterior  surface,  and 
runs  towards  the  proximal  end  of  the  bone.  The  head  of  the  hone  is  supplied 
by  the  radial  recurrent  and  interosseous  recurrent  arteries.  The  lower  end  is 
supplied  by  the  anterior  and  posterior  interosseous  arteries  and  numerous 
twigs  from  carpal  arches. 

LESSON  XVII 

The  Ulna  (Plates  XXIY-XXY.)  is  the  longer  of  the  two  bones  of  the  fore- 
arm; its  proximal  extremity  islarger  than  that  of  the  radius,  while  its  distal  ex- 
tremity is  smaller  than  that  of  the  radius.  On  cross  section  it  is  triangular,  but  its 
distal  part  is  more  circular.  It  has  a  proximal  and  distal  extremity  and  a  dia- 
physis.  The  proximal  extremity  has  the  olecranon  process  and  the  greater 
and  lesser  sigmoid  cavities.  The  olecranon  (meaning  head  of  elbow)  is  con- 
cave from  above  down,  and  convex  transversely  on  its  articular  surface1  which 
is  covered  with  cartilage  in  the  recent  state.  Its  margins  give  attachment  to 
the  capsular  ligament  of  the  elbow.  This  surface  makes  the  greater  part  of 
the  greater  sigmoid  cavity.  On  its  inner  surface  is  a  tubercle  for  the  ulnar 
origin  of  the  Flexor  carpi  ulnaris.  The  internal  lateral  ligament  has  an  attach- 
ment in  front  of  the  tubercle.  The  other  surface  gives  attachment  to  part  of 
the  Anconeus. 

The  extremity  of  the  process  fits  into  the  olecranon  fossa  of  the  ulna  when 
the  arm  is  extended.  Its  upper  surface  has  a  concave  impression  for  the  ten- 
don of  the  Triceps  and  the  anterior  margin  for  the  posterior  ligament.  The 
posterior  surface  is  covered  by  a  bursa.  The  coronoid  (like  a  crown)  makes 
the  lower  part  of  the  greater  sigmoid  cavity  and  the  upper  pari  of  the  bone. 

Its  upper  surface  is  covered  with  cartilage  in  the  recent  state.  When  the 
arm  is  flexed  it  fits  in  the  coronoid  impression  of  the  humerus.  <>n  its  outer 
surface  is  the  lesser  sigmoid  cavity  for  the  head  of  the  radius.  The  orbicular 
ligament  is  attached  to  the  margin  of  the  lesser  sigmoid  cavity. 

On  it>  inferior  surface  is  an  impression  for  the  insertion  of  the  Brachialis 
anticus.  Where  it  joins  the  shaft  of  the  ulna  is  the  tubercle  for  the  attach- 
ment of  the  oblique  ligament.  On  the  inner  surface  is  the  attachment  of  the 
internal  ligament,  one  attachment  for  tin-  Flexor  sublimis  digitorum;  Behind 
this  is  a  depression  for  the  attachment  of  the  flexor  profundus  digitorum,  anddis- 
lally  from  this  one  for  the  Pronator  radii  teres,  and  occasionally  one  attach- 
ment  for  the  Flexor  longus  pollicis. 

The  greater  and  lesser  sigmoid  cavities  have  been  described  with  these  two 
processes.  The  diaphysis  has  three  borders  and  three  surfaces.  The  anterior 
border  extends  from  the  inner  angle  of  the  coronoid  process  to  the  from  of  the 
styloid  process;  for  most  of  the  extent  it  is  smooth  and  rounded.  It  separates 
the  anterior  and  internal  surfaces  andgives  attachment  to  the  Flexor  profundus 


76  ANATOMY    IN   A    NUTSHELL. 

digitorum  proximally,  and  the  Pronator  quadratus  distally.  The  posterior 
border  commences  at  the  apex  of  a  triangular  subcutaneous  surface  at  the  back 
of  the  olecranon  and  continues  to  the  back  part  of  the  styloid  process.  It  is 
well  marked  in  the  proximal  three-fourths  and  gives  attachment  to  the  common 
aponeurosis  which  has  three  muscles  attached  to  it.  viz..  the  Extensor  carpi 
ulnaris,  Flexor  carpi  ulnaris  and  Flexor  profundus  digitorum.  This  border 
separates  the  internal  and  posterior  surfaces.  The  outer  or  interosseous  bor- 
der, is  divided  above,  extending  to  the  anterior  and  posterior  extremities  of 
the  sigmoid  cavity;  embracing  the  triangular  depression  (the  bicipital  hollow). 
In  the  trout  part  of  this  impression  lodges  the  tubercle  and  tendon  of  the  Bi- 
ceps, when  the  arm  is  pronated,  and  the  back  part  gives  attachment  to  the 
Supinator  brevis.  It  separates  the  anterior  and  posterior  surfaces.  To  its 
distal  four-fifths  is  attached  the  interosseous  membrane.  The  anterior  sur- 
face is  grooved  in  the  proximal  three-fourths  of  its  extent,  which  is  broader 
than  the  distal  portion,  and  gives  attachment  to  the  Flexor  profundus  digi- 
torum. Its  distal  one-fourth  gives  attachment  to  the  Pronator  quadratus. 
The  pronator  ridge,  or  oblique  line,  is  directed  distally  and  inward  at  the  prox- 
imal limit  of  the  Pronator  quadratus. 

The  nutrient  foramen  is  on  this  surface  at  the  junction  of  the  proximal  one- 
third  with  the  middle  one-third,  and  is  directed  towards  the  elbow.  The  nutri- 
ent artery  is  a  branch   of  the  anterior  interosseous. 

The  internal  surface  is  broad  and  concave  proximally.  narrow  and  convex 
distally.  The  proximal  three-fourths  gives  attachment  to  the  Flexor  profun- 
dus digitorum,  whereas  the  distal  one-fourth  is  subcutaneous.  The  posterior 
surface  is  broad  and  concave  proximally,  narrow  and  convex  in  the  middle. 
narrow,  smooth,  and  round  distally.  It>  oblique  line  runs  from  the  posterior 
extremity  of  the  lesser  cavity  distally  to  the  posterior  border.  The  first  part 
of  this  line  gives  attachment  to  the  Supinator  brevis.  The  triangular  surface 
between  this  line  and  the  elbow  receives  the  insertion  of  the  Anconeus.  The 
"Uter  portion  of  this  surface  gives  attachment  to  the  Supinator  brevis.  Ex- 
tensor ossis  metacarpi  pollicis,  Extensor  Longus  pollicis,  and  Extensor  indicis. 
The  inner  portion  is  smooth,  being  covered  with  the  Extensor  carpi  ulnaris.  A 
perpendicular  ridge  separates  these  two  portions  of  this  surface. 

The  lower  extremity  is  small  ami  consists  of  two  parts,  a  head  and  styloid 
process.  '  m  the  articular  surface  they  are  separated  by  a  groove  which  re- 
ceive- the  apex  of  the  interarticular  fibro-cartilage,  thus  separating  the  ulna 
from  the  wrist-joint.  The  margin  of  the  head  is  received  in  the  sigmoid  cavity 
of  the  radius  and  the  styloid  process  is  a  continuation  of  the  posterior  border 
projecting  from  the  inner  and  back  part  of  the  bone.  Its  apex  gives  attach- 
ment to  the  internal  lateral  ligament;  it>  posterior  surface  is  grooved  for  the 
Extensor  minimi  digiti. 

Ossifk  ITION.  From  three  center-,  one  for  the  shaft  about  the  eighth 
week,  one  tor  the  distal  extremity  about  the  fourth  year  which  joins  the  shaft 
the  eighteenth  or  twentieth  year,  and  one  tor  the  proximal  extremity  the 
tenth  year  which  join-  the  shaft  the  sixteenth  or  seventeenth  year. 

Ai:t)<  i  lation.-    It  articulates  with  the  humerus  and  radius. 


ANATOMY    IN    A    NUTSHELL. 


77 


Muscles. — It  has  fourteen  muscles  attached,  Triceps,  Anconeus,  Flexor 
carpi  ulnaris,  Brachialis  anticus,  Supinator  brevis.  Flexor  sublimis  digitorum, 
Flexor  profundus  digitorum,  Pronator  quadratus,  Extensor  carpi  ulnaris 
Pronator  radii  teres,  Extensor  ossis  metacarpi  pollicis,  Extensor  longus 
pollicis,  Extensor  indicis,  and  Flexor  longus  pollicis. 

PLATE  XXV III 

DORSALIS  SCAPULAE  ARTERY 


GREAT  TUBEROSITY 


POST.  CIRCUMFLEX  ARTERY 


CIRCUMFLEX  N 


MUSCULO-SPIRAL  N  — 


THE  QUADRILATERAL  SPACE  IS 
BOUNOED  ABOVE  BY  THE  TERES  MINOR;  BELOW  BY  THE 
TERES  MAJOR;  EXTERNALLY  BY  THE  HUMERUS;  INTER- 
NALLY BY  THE  LONG  HEAD  OF  THE  TRICEPS.  IT  HAS  THE 
CIRCUMFLEX  N.  AND  THE  POST.  CIRCUMFLEX  ARTERY 
PASSING  THROUGH  IT.  THERE  ARE  TWO  TRIANGUAL 
SPACES  FORMED  BY  THESE  SAME  BOUNDARIES.  ONE 
TRIANGLE  HAS  THE  MUSCULO-SPIRAL  N.  PASSING 
THROUGH  IT.  AND  IS  BOUNDED  ABOVE  BY  THE  TERES 
MAJOR,  EXTERNALLY  BY  THE  HUMERUS.  INTERNALLY  BY 
THE  LONG  HEAD  OF  TRICEPS.  THE  OTHER  TRIANGLE  HAS 
THE  DORSALIS  SCAPULAE  ARTERY  PASSING  PARTLY 
THROUGH  IT  AND  THEN  PASSING  BETWEEN  THE  SCAPULA 
AND  THE  TERES  MAJOR  INTO  THE  INFRASPINOUS  FOSSA. 


Showing  the  Quadrilateral  Space  and  Structures  Passing  Through  it 


Blood  Supply. — The  nutrienl  vessel  enters  the  shaft  near  the  middle  of 
the  anterior  surface;  it  is  derived  from  the  anterior  interosseous  trunk,  and  is 
directed  towards  the  proximal  end.  The  upper  extremity  receives  branches 
from  the  anterior  and  posterior  ulnar  recurrent  and  from  the  interosseous  re- 
current. The  lower  end  receives  twigs  from  the  anterior  and  posterior  inter- 
osseous arteries. 


7S  ANATOMY    IN    A    NUTSHELL. 

LESSON  XVIII. 

The  wrist-joint  is  a  condyloid  joint  (Plate  XL)  having  all  movements  ex- 
cept axial  rotation.  It  is  formed  by  the  lower  head  of  the  radius  and  the  inter- 
articular  fibro-cartilage  proximally  and  the  scaphoid,  semilunar,  and  cuneiform 
bones  distally.  The  ulna  docs  not  go  into  the  joint,  being  separated  by  the 
interarticular  fibro-cartilage  from  the  done-  of  the  wrist. 

The  ligaments  of  this  joint  arc  the  anterior,  posterior,  internal  lateral,  and 
external  lateral  which  make  a  capsular  ligament.  The  anterior  ligament  ex- 
tend- from  the  anterior  surface  of  the  lower  border  of  the  ulna  to  the  front  of 
the  interarticular  fibro-cartilage,  also  from  the  anterior  surface  of  the  lower 
border  of  the  radius  and  its  styloid  process,  to  the  palmar  surface  of  the  scap- 
hoid, semilunar,  and  cuneiform  bones  distally,  some  fibers  continuing  to  the  c* 
magnum  and  the  unciform  hones.  There  are  some  superficial  fibers  passing 
from  the  styloid  process  ^i  the  ulna  to  the  semilunar  and  cuneiform.  This 
ligamenl  is  pierced  by  small  vessels.  The  posterior  ligament  is  weaker  than  the 
anterior  one:  it  extend-  from  the  posterior  surface  of  the  lower  part  of  the  radius 
and  the  triangular  interarticular  fibro-cartilage  to  the  posterior  surface  of  the 
scaphoid,  semilunar  and  cuneiform  bones.  The  internal  lateral  ligament  ex- 
tends from  the  tip  of  the  styloid  process  of  the  ulna  to  the  inner  surface  of  the 
cuneiform,  by  one  of  its  divisions,  and  to  the  pisiform  and  annular  ligament  by 
the  other.  The  external  lateral  ligament  extends  from  the  styloid  process  of 
the  radius  to  the  outer  side  of  the  scaphoid,  some  fibers  continuing  to  the  trape- 
zium and  annular  ligament. 

A  synovial  membrane  which  is  very  lax  and  does  not  communicate  with 
the  joint  above  and  below,  lines  the  ligaments  of  this  joint.     (Plate  XLII.) 

The  nerve  supply  is  the  ulnar,  anterior  and  posterior  interosseous. 

The    blood  supply  is  the  anterior    and  posterior  interosseous,    anterior  and 

erior  carpal  arches,  and     recurrent  branches  from  the  dee])  palmar  arch. 

The  superior  radio-ulnar  articulation  is  a  trochoides,  and  is  formed  by  the 
head  of  the  radius  and  the  lesser  sigmoid  cavity  of  the  ulna.  Its  only  liga- 
menl i-  the  orbicular,  which  surrounds  the  head  of  the  raidus.  It  is  connected 
io  the  anterior  and  posterior  borders  of  the  lesser  sigmoid  cavity,  and  with  it 
make-  a  complete  ring.  It-  lower  circumference  is  less  than  that  of  the  upper, 
thus  holding  the  head  <<\  the  radius  in  position.  It  blends  with  all  the  liga- 
ments of  the  elbow,  except  the  internal:  the  synovial  membrane  continues  with 

that    of   the  elbow. 

The  middle  radio-ulnar  articulation  has  two  ligaments:  first,  the  oblique 
..i-  round  ligament  which  passes  distally  and  outward  from  the  base  of  the 
coronoid  process  to  the  bicipital  tuberosity  of  the  radius.  This  ligament  is 
often  absent.  Second,  the  interosseous  membrane,  passing  between  the  two 
adjacent  border-  of  the  radius  and  ulna:  its  liber-  pass  distally  and  inward.  It 
commences  beyond  the  bicipital  tuberosity  of  the  radius  and  extends  almost  to 
the  di-tal  extremity  of  the  two  bones.  It  affords  attachment  to  the  muscles. 
The  anterior  interosseous  artery  passes  to  the  back  of  the  forearm,  between  the 
radius  and  ulna  beyondthis  membrane.   The  posterior  interosseous  vessels  pass 


ANATOMY    IN    A    NUTSHELL.  79 

to  the  back  of  the  forearm  between  the  radius  and  ulna  above  this  membrane. 

The  inferior  radio-ulnar  articulation  is  a  trochoides,  and  is  formed  by  the 
head  of  the  ulna  and  the  sigmoid  cavity  of  the  raidus  and  fibro-cartilage.  Its 
ligaments  are  the  anterior  and  posterior  radio-ulnar  which  make  the  capsular 
ligament.  The  anterior  radio-ulnar  ligament  passes  from  the  front  border  of 
the  sigmoid  cavity  of  the  radius  to  the  anterior  surface  of  the  head  of  the  ulna. 
The  posterior  one  is  a  similar  ligament  on  the  posterior  surface.  The  triangular 
interartieular  fibro-cartilage  is  at  the  lower  end  of  the  ulna,  between  the  styloid 
process  and  the  radius.  Its  perimeter  is  attached  to  the  ligaments  of  the  wrist; 
it  is  attached  by  its  apex  to  the  depression  between  the  head  and  styloid  pro- 
cess of  the  ulna,  by  its  base  to  the  lower  end  of  the  radius.  Sometimes  it  is 
perforated,  in  such  a  case  the  synovial  membrane  communicates  with  that  of 
the  wrist. 

The  blood  supply  is  the  anterior  interosseous  and  anterior  carpal  arch. 

The  nerve  supply  is  the  anterior  and  posterior  interosseous.  Synovial 
membrane,  the  membrana  sacciformis,  lines  the  adjacent  surfaces  of  the  ulna 
and  the  interartieular  fibro-cartilage.  and  the  ulna  and  the  radius.  As  stated 
before,  it  sometimes  communicates  with  the  wrist-joint. 

j  Brachialis  amicus. — Description. — (Plate  XVI.) — This  is  a  broad  muscle 
which  covers  the  elbow-joint  and  the  lower  half  of  the  front  of  the  humerus. 
It  is  somewhat  compressed  from  before  backward  and  is  broader  in  the  middle 
than  at  either  extremity.  Its  fibers  converge  to  a  thick  tendon.  The  outer 
border  of  the  muscle  is  in  relation  with  the  musculo-spiral  nerve  and  radial  re- 
current artery. 

Origin. — (1)  Lower  half  of  outer  and  inner  surfaces  of  shaft  of  humerus; 
(2)  intermuscular  septa;  (3)  commences  above  at  insertion  of  Deltoid  and  ex- 
tends below  to  within  one  inch  of  margin  of  articular  surface.      (Plate  XXIII.) 

Insertion. — Into  a  rough  depression  on  the  anterior  surface  of  the  coron- 
noid  process  of  the  ulna,  being  received  into  an  interval  between  two  fleshy 
slips  of  the  Flexor  profundus  digitorum,     (Plate  XXV.) 

Action. — Flexor  of  forearm. 

Nerve  Supply. — Fifth  and  sixth  cervical  through  the  musculo-cutaneous 
and  musculo-spiral. 

Blood  Si  pply.-   Brachial  artery. 

Subanconeus.  Description.-  The  Subanconeus  is  a  name  given  to  a  few 
fibers  from  the  under  surface  of  the  lower  pai  I  of  the  Triceps  muscle.  By  some 
authors  it  is  regarded  as  the  analogue  of  the  Stfbcrureus  in  the  lower  limb,  but 
it  is  not    a  separate  muscle. 

Origin. — Humerus  above  olecranon  fossa. 

Insertion.     Posterior  ligament  of  elbow-joint. 

A<  tion.     1  >raws  up  posterior  ligamenl  during  extension  of  forearm. 

Nerve  Supply.  —Musculo-spiral. 

Blood  Supply.     Brachial  artery. 

Pronator  radii  teres.  Description.  (Plate  KXIX.)  This  muscle 
arises  by  two  heads,  beiween  which  the  median  nerve  enters  the  forearm. 
It  passes  obliquely  across  the  forearm  from  the  inner  to  the  outer  side,  and  ter- 


PLATE  XXIX 


LUMBRICALES 
ABDUCTOR  INDICIS 

FLEXOR  LONG 
US   POLLICIS       i 

ADDUCTOR  IRANS 
VETSE  POLLICIS 

FLEXOR    BREYIS 
POLLICIS 

ABDUCTOR    POLLICIS 
OPPONENS    POLLICIS 

POST.  ANNULAR  LIGT 

EXTENSOR  BREVIS  POLLICtS 

EXTENSOR  OSSIS 
METACARPI    POLLICIS 
FLEXOR  LONGUS  POLLICIS 


•SUPINATOR   LONGUS 


LEXOR    PROFUNDUS 
DIGITORUM. 


FLEXOR  SUBLIMIS 
DIGITORUM 

DIGITAL  ARTERIES^DIGITALtJEKVE 

SUPERFICIAL  TRANSVERSE  LIGT. 

—  FLEXOR  BREVIS  MINIMI  DI&ITI. 

ABDUCTOR  MINIMI  DIGIT!. 

PALMARIS    BREVIS 

PISIFORM   BONE 

ANT.  ANNULAR    LIG-'T- 


FLEXOR   SUBLIMIS  DIGITORUM: 


-FLEXOR  CARPI    ULNARIS 


PALMARIS  LONGUS. 


FLEXOR  CARPI  RADIALIS. 


PRONATOR   RADII  TERES. 


BRACHIALIS  ANTICUS. 


BICEPS 


TRICEPS. 


Muscles  of  the  Left  Forearm     First  Layer— Anterior  View 

80 


ANATOMY    IN    A    NUTSHELL.  81 

minates  in  a  flat  tendon  which  turns  over  the  outer  margin  of  the  radius. 

Origin. — One  head.  (1)  immediately  above  internal  condyle  of  humerus: 
(2)  common  tendon:  (3)  fascia;  i4i  intermuscular  septum.  The  other  head, 
thin  fasciculus  from  inner  side  of  coronoid  process  of  ulna,  joining  first  head  at 
an  acute  angle.      (Plate  XXIII.) 

Insertion. — Rough  impression  on  middle  of  outer  surface  of  shaft  of 
radius.      (Plate  XXV.) 

A'  tii»n. — To  pronate  hand. 

Nerve  Supply. — Median. 

Blood  Supply. — Radial  artery. 

Flexor  carpi  radialis. — Description. — (Plate  XXIX.) — This  muscle  lies 
on  the  inner  side  of  the  preceding  muscle.  It  is  slender  and  aponeurotic  in 
structure  at  its  commencement  above,  but  increases  in  size  and  terminates  in 
a  tendon  which  forms  rather  more  than  the  lower  half  of  its  length.  This  tendon 
3£  s  through  a  canal  on  the  outer  side  of  the  annular  ligament  and  runs 
through  a  groove  in  the  os  trapezium.  The  radial  artery  lies  between  the  ten- 
don and  the  Supinator  longus  muscle,  and  may  easily  be  tied  in  this  situation. 

Origin. — (1)  Internal  condyle  by  common  tendon:  (2)  fascia;  (3)  inter- 
muscular septum.     (Plate  XXIII. 

Insertion. — (Plate  XXYII.) — Bases  of  metacarpals  of  index  and  middle 
finger.-. 

Action. — Flexor  of  wrist. 

Nerve  Supply. — Median. 

Blood  Supply. — Radial  arterv. 


LESSON  XIX. 

Palmaris  longus. — Description. — (Plate  XXIX.)— Thi-  is  a  slender, 
fusiform  muscle  lying  on  the  inner  side  of  the  preceding.  It  is  often  absent 
and  is  subject  to  much  variation:  it  may  be  tedinous  above  and  muscular 
below:  or  it  may  be  muscular  in  the  center  with  a  tendon  above  and  below; 
or  it  may  present  two  muscular  bundles  with  a  central  tendon:  or  finally,  it 
may  consist    simply  of  a  mere  tendinous  band. 

Origin. — (1)  Inner  condyle  of  humerus  by  the  common  tendon:  (2)  deep 
fascia:  (3)  intermuscular  septa.      (Plate   XXIII.) 

Insertion. — Palmar  fascia  and  occasionally  a  Tendinous  ligamenl  to  shorl 
muscles  of  thumb.     (Plate  XXIX 

\<  tion. — Tenses  palmar  fascia. 

\i:i;\  i:  Supply. — Median. 

Blood  Supply.  —  Radial  and  ulnar  arteries. 

Flexor  carpi  ulnarls. — Description.-  Tins  muscle  lie-  along  the  ulnar 
Bide  ^i  the  forearm.  It  arises  by  two  head-  connected  by  a  tendinous  arch, 
beneath  which  pass  the  ulnar  nerve  and  posterior  ulnar  recurrent  artery.  The 
fibers  terminate  in  a  tendon  which  occupies  the  anterior  part  of  the  lower  half 
of  the  muscle.  The  ulnar  artery  lies  on  the  outer  side  of  this  tendon,  in  the 
lower  two-thirds  of   the  forearm.      (Plate-    XXIX-.W 


82  ANATOMY    IN    A    NUTSHELL. 

Origin.— One  head  from  internal  condyle  of  humerus  by  common  tendon; 

the  other  from  inner  margin  of  olecranon,  upper  two-thirds  of  posterior  border 
of  ulna  by  an  aponeurosis  common  to  it,  the  Extensor  carpi  ulnaris,  and  Flexor 
profundus  digitorum,  and  also  from  the  intermuscular  septum.  (Plate  XXIII.) 

Insertion.  Pisiform  bone,  annular  ligament,  and  base  of  fifth  meta- 
carpal and  unciform  bones.     (Plate  XXVII.) 

Ai  in i\.     Flexes  wrisi . 

\'u;\  i:  Si  imma  .      Ulnar. 

Blood  Supply.     Ulnar  artery. 

Flexor  sublimis  digitorum  (perforatus).  Description.— (Plates  XXX.) 
This  muscle  lies  just  beneath  the  preceding  and  is  the  largest  of  the 
muscles  of  the  superficial  layer.  It  arises  by  three  heads.  The  fibers 
pass  vertically  downward,  forming  a  broad  and  thick  muscle  which  speedily 
■  livides  into  two  planes  of  muscular  fibers,  superficial  and  deep.  The  super- 
ficial plane  divides  into  two  parts  which  end  in  tendonsfor  the  middle  and  ring 
fingers;  the  deep  plane  also  divides  into  two  parts  which  end  in  tendons  for  the 
index  and  little  fingers,  hut  previous  to  having  done  so  it  gives  off  a  muscular 
slip  which  joins  that  part  of  the  superficial  plane  which  is  intended  for  the  ring 
finger.  As  the  four  tendons  thus  formed  pass  beneath  the  annular  ligament 
into  the  palm  of  the  hand  they  are  arranged  in  pairs,  the  superficial  pair  cor- 
responding to  the  middle  and  ring  fingers,  the  deep  pair  to  the  index  and  little 
fingers.  The  tendons  diverge  as  they  pass  onward.  Opposite  the  bases  of 
the  first  phalanges  each  tendon  divides  into  two  slips  to  allow  the  passage  of 
the  corresponding  tendon  of  the  Flexor  profundus  digitorum:  the  two  portions 
then  unite  and  form  a  grooved  channel  for  the  reception  of  the  deep  flexor 
tendon.      Finally  they  subdivide  a  second  time  prior  to  their  insertion. 

Origin.  (By  three  heads)  first  head,  (1)  internal  condyle  of  humerus  by 
common  tendon;  (2)  internal  lateral  ligament  of  elbow-joint;  ami  (3)  inter- 
muscular septum.  Second  head,  inner  side  of  coronoid  process  of  ulna.  Third 
head,  oblique  line  of  radius,  from  the  tubercle  to  the  insertion  of  the  Pronator 
radii  ten-.     (Plates  XXV-XXIII.) 

1  nsertion.  t  Plate  XXVII.)-  Lateral  margins  of  second  phalanges  about 
their  middle. 

Action.     Flexes  second  phalanges. 

\'u;\  i.  Si  ppl"5  .      Median. 

Hi.< Supply.     Radial  and  ulnar  arteries. 

Flexor  profundus  digitorum.  Description.— (Plate  XXXI.)  This  muscle 
is  situated  on  the  ulnar  side  of  the  forearm,  immediately  beneath  the  su- 
per fiicial  flexors.  Its  fibers  form  a  fleshy  belly  of  considerable  size  which 
divides  into  four  tendons;  these  pass  under  the  annular  ligament  beneath  the 
tendons  of  the  Flexor  sublimis  digitorum.  Opposite  the  first  phalanges  the 
tendons  pass  through  the  openings  in  the  two  slips  of  the  tendons  of  the  Flexor 
sublimis  digitorum.  The  portion  of  the  muscle  for  the  index  finger  is  usually 
distinct  throughout,  bu1  the  tendons  for  the  three  inner  fingers  are  connected 
together  by  cellular  tissue  and  tendinous  slips  as  far  as  the  palm  of  the  hand. 
Four  Bmall  muscles,  the  Lumbricales,  are  connected  with  the  tendons  of  the 
Flexor  profundus  in  the  palm. 


PLATE  XXX 


SUPERFICIAL  TRANSVERSE  LIGAMENT 

LUMBRICALIS. 
RADIAL  PORTION  OF  PALMAR  BURSA, 


INNER  H 
FLEXOR  BREVIS  P0LLIC1S. 
OUTER  HEAD 

tBDUCTOR  POLLICIS. 


EXTENSOR    BRE'.IS   POLLICIS 
EXTENSOR  OSSIS  WETACARPI  POLLICIS 


FLEXUS  LONGUS  POLLICIS 


EXTENSOR  CARPI  RAO.ALIS  LONGIOR 


SUPINATOR  BREVIS 


DEEP  TRANSVERSE  LIGAMENT. 

~      ULNAR  PORTION  OF  PALMAR  BURSA. 
PALMARIS  BREVIS. 

CPPONENS  MINIMI  OIGITI 

ADDUCTOR  MINIMI  DIGIT! 


ANTERiOR  ANNULAR  LIGAMENT. 
DEEP  FASCIA  OF  FOREARM. 


FLEXOR  V.BLIMlSDIWTORUM. 


)  RSDIAU 


Wi    ',J.     -        \    I.  '  FLEXOR  CARPI  ULNARls 

Vim  u 

FLEXOR  CARPI  RADlAllS 
PRONATOR  RAlu 


BRALhIALIS  AMICUS 


w 

[bicep:  _ 

l 

Muscles  op  the   Left  Forearm     Second  Layer     Anterior  \  n\\ 

83 


ANATOMY    IN    A    NUTSHELL. 

Origin.  (1)  Upper  three-fourths  of  shaft  of  ulna,  anterior  and  inner  sur- 
faces; (2)  depression  ob  inner  side  of  coronoid  process;  (3)  by  aponeurosis 
from  upper  three-fourths  of  posterior  border  of  ulna;  and  (4)  ulnar  half  of  in- 
terosseous membrane.      (Plate  XXV.) 

Insertion.     Bases  of  last  phalanges.     (Plate  XXVII.) 

\.  noN.     Flexes  phalanges. 

\ii;\i  Supply.  Eighth  cervical  and  first  dorsal  through  ulnar,  and  the 
anterior  interosseous  branch  of  median. 

Blood  Si  ppli  .     Ulnar  artery. 

Flexor  Longus  pollicis. — Description. — (Plate  XXXI.) — This  muscle  is 
situated  od  the  radial  side  of  the  forearm,  lying  on  the  same  plane  as  the 
preceding  .  The  fibers  pass  downward  and  terminate  in  a  flattened  tendon 
which  passes  beneath  the  annular  ligament  and  is  then  lodged  in  the  interspace 
between  the  outer  head  of  the  Flexor  brevis  pollicis  and  the  Adductor  obliqus 
pollicis.  The  anterior  interosseous  vessels  and  nerve  lie  between  this  muscle 
and    the    Flexor  profudus   digitorum. 

Origin.-  Front  the  grooved  anterior  surface  of  the  shaft  of  the  radius, 
from  the  tuberosity  and  oblique  line  to  within  a  short  distance  of  the  Pronator 
quadratus;  also  from  the  adjacent  part  of  the  interosseous  membrane,  and  gen- 
erally by  a  fleshy  slip  from  the  inner  border  of  the  coronoid  process  of  ulna,  or 
from  the  internal  condyle  of  the  humerus.      (Plate   XXV.) 

Insertion.-  Base  of  last  phalanx  of  thumb.     (Plate  XXVII.) 

\«  tion.     Flexes  thumb. 

Nerve  Supply.-  Eighth  cervical  and  first  dorsal  through  the  anterior 
interosseous  branch  of  the  median. 

Blood  Supply.-   Radial  artery. 

Pronator  quadratus.— Description. — (Plate  XXXI.) — This  is  a  small, 
flat,  quadrilateral  muscle  extending  transversely  across  the  front  of  the  radius 
and  ulna,  above  their  carpal  extremities. 

Origin.  (1)  Oblique  ridge  on  lower  part  of  anterior  surface  of  ulna;  (2) 
l"\\er  fourth  of  anterior  surface  and  anterior  border  of  ulna;  and  (3)  strong 
aponeurosis  covering  inner  third  of  muscle.     (Plate  XXV.) 

Insertion.  (Plate  XXV.)-  Lower  fourth  of  anterior  surf  ace  and  anterior 
border  of  shaft  of  radius. 

\<  I  [ON.      Pronates  the  hand. 

Nerve  Supply.  Eighth  cervical  and  first  dorsal  through  anterior 
interosseous  branch  <<\'  median. 

Blood  Supply.     Radial   and   ulnar  arteries. 

LESSON   XX. 

Supinator  longus.  Description.  (Plate  XXXII.)— The  Supinator  longus 
(Brachio-radialis)  is  the  mosl  superficial  muscle  on  the  radial  side  of  the 
forearm;  it  is  fleshy  for  the  upper  two-thirds  of  its  extent,  tendinous  below,  the 
tendon  commencing  above  the  middle  of  the  forearm.  Its  inner  border,  above 
the  elbow,  is  in  relation  with  the  musculo-spiral  nerve  and  radial  recurrent 
artery,  and  in  the  forearm  with  the  radial  vessels  and  nerve. 


ANATOMY    IN    A    NUTSHELL.  85 

Origin. — Upper  two-thirds  of  external  supracondylar  ridge  of  humerus 
and  external  intermuscular  septum.      (Plate  XXIII.) 

Insertion. — Outer  side  of  base  of  styloid  process  of  raidus.     (Plate  XXV. 

Action. — Supinates  hand. 

Nerve  Supply. — Sixth  cervical  through  the  musculo-spiral  nerve. 

Blood  Supply. — Brachial  and  radial   arteries. 

Extensor  carpi  radialis  longior. — Description. —  (Plate  XXXII.)  — 
This  muscle  lies  partly  beneath  the  Supinator  longus,  its  fibers  terminating 
at  the  upper  third  of  the  forearm  in  a  flat  tendon  which  runs  along  the 
outer  border  of  the  radius  beneath  the  extensor  tendons  of  the  thumb.  It 
then  passes  through  a  groove  common  to  it  and  the  Ex'.ensor  carpi  radialis 
brevior.  immediately  behind  the  styloid  process  of  the  radius. 

Origin. — From  the  lower  third  of  the  external  supracondylar  ridge  of  the  hu- 
merus and  from  the  external  intermuscular  septum  by  a  few  fibers  from  the 
common  tendon  of  origin  of  the  extensor  muscles  of  the  forearm.  (Plate  XXIII.) 

Insertion. — Base  of  metacarpal  of  index  finger,  radial  side.  (Plate  XXVI.) 

Action. — Extends  the  wrist. 

Xerve  Supply. — Sixth  and  seventh  cervical  through  the    musculo-spiral. 

Blood  Supply. — Radial  artery. 

Extensor  carpi  radialis  brevior. — Description. — (Plates  XXXII.) — 
This  muscle  is  shorter  and  thicker  than  the  preceding,  beneath  which  it  is 
placed.  Its  fibers  terminate  about  the  middle  of  the  forearm  in  a  flat  ten- 
don which  is  closely  connected  with  that  of  the  Longior,  and  accompanies 
it  to  the  wrist,  lying  in  the  same  groove  on  the  posterior  surface  of  the  radius; 
it  passes  beneath  the  extensor  tendons  of  the  thumb,  then  beneath  the  annular 
ligament. 

The  tendons  of  the  two  preceding  muscles  pass  through  the  same  com- 
partment of  the  annular  ligament  and  are  lubricated  by  a  single  synovial  mem- 
brane, but  are  separated  from  each  other  by  a  small  vertical  ridge  of  bone  as 
they  lie  in  the  groove  at  the  back  of  the  radius. 

Origin. — From  the  external  condyle  of  the  humerus  by  a  tendon  common 
to  it  and  the  three  following  muscles:  from  the  external  lateral  ligament  of  the 
elbow-joint,  from  a  strong  aponeurosis  which  covers  its  surfaces,  and  from  the 
intermuscular  septa.     (Plate  XXIII.) 

Insertion. — (Plate  XXVT.) —  Base  of  metacarpal  bone  of  middle  finger 
on  its  radial  side. 

Action. — It  assists  the  Extensor  carpi  radialis  longior  in  extending  the 
wrist  and  may  also  act  slightly  as  an  abductor  of  the  hand. 

Nerve  Supply. — Sixth  and  seventh  cervical  through  the  posterior  inter- 
osseous. 

Blood  Supply. — Radial  artery. 

Extensor  communis  dijritoruni. —  Description.  (Plates  XXXII.) — This 
muscle  is  situated  at  the  back  part  of  the  forearm  and  divides  just  below  the 
middle  into  three  fleshy  masses,  from  which  tendons  proceed;  these  pass  to- 
gether with  the  Extensor  indicis  through  a  separate  compartment  of  the  annu- 
lar ligament.     The  tendons  then  diverge,  the  innermost  one  dividing  into   two. 


PLATE  XXXI 


FLEXOR  SUBLIMIS  WGITOHtM 


•U6A*ENTUm  VA6INALE, 
FIRST  LUMBRICALIS 
FIRST  DORSAL  INTEROSSEOUS 
TRANSVERSE 
ADDUCTOR  POLLICIS. 
OBLIQUE 


(OUTER  HEAD)  (0) 
FLEXOR  BRE\ IS  POLLICIS 
(INNER  MtADI  (I,. 


/.BDUCTOR  POLUCIS 


FLEXOR  PRORINOUS  DtGITORUM 


FLEXOR  BREVIS  MINIMI  DIGJTI 


PALMARIS  BREVIS 

FLEXOR  SUBLIHtUS  WGITOROW 

ABDUCTOR  MINIMI  DIGITI 

DEEP  FASCIA  OF  FORLARM 


EKTINSCR  CARPI  RADVALIS     LONGIOR. 


J.JPINATOS  BREVIS 


M  ,  fl/j,  \\m    :\\    V  ■       FUXOR  PROFUNDUS  DI&ITORUM 

Mtt'<  .it1?  (ill :.»!'>  : 


FLEXOR  SUBLIMIS  DIGITORIUM 


BRACHlO-RI.DIALlS 


FLEXOR  CARPI  ULNARIS 

PALMARIS  LONGUS. 
FLEXOR  CARPI  RADIALIS 
PRONATOR  RADII  TERES 


'X   v.- 

m       m 

m 

I  jfl  ,  BRACHIALIS  ANTIC!';,  ',1      Ml,  K 

I  Li         I        /  T'4  M    "'  -^TRICEPS 

m 

MuscLESfOF  theJLept  F(  m  i,  uim— Third  and  Fourth  Layers— Anterior  View 

86 


ANATOMY    IN    A    NUTSHELL.  87 

Each  tendon  opposite  the  metacarpophalangeal  articulation  becomes  nar- 
row and  thickened  and  gives  off  a  thin  fasciculus  upon  each  side  of  the 
joint,  which  blends  with  the  lateral  ligament  and  serves  as  a  posterior  lig- 
ament; after  having  passed  the  joint  it  spreads  out  into  a  broad  aponeurosis 
which  covers  the  whole  of  the  dorsal  surface  of  the  first  phalanx,  being  rein- 
forced in  this  situation  by  the  tendons  of  the  Interossei  and  Lnmbricales. 
Opposite  the  first  phalangeal  joint  this  aponeurosis  divides  into  three  slips,  a 
middle  and  two  lateral. 

Origin. — (1)  External  condyle  of  humerus  by  common  tendon;  (2)  deep 
fascia;   (3)  intermuscular  septum.     (Plate  XXIII.) 

Insertion. — Into  the  second  and  third  phalanges  of  the  fingers  in  the  fol- 
lowing manner;  the  outermost  tendon  accompanied  by  the  Extensor  indicis, 
goes  to  the  index  finger;  the  second  tendon  is  sometimes  attached  to  the  first  by  a 
thin  transverse  band  and  receives  a  slip  from  the  third  tendon ;  it  goes  to 
the  middle  finger;  the  third  tendon  gives  off  a  slip  to  the  second  and  receives 
a  very  considerable  part  of  the  fourth  tendon ;  the  fourth  or  innermost 
tendon,  after  dividing,  sends  one  slip  to  join  the  third  tendon;  the  other,  rein- 
forced by  the  Extensor  minimi  digiti,  goes  to  the  little  finger.  After  the  di- 
vision of  the  aponeurosis  opposite  the  phalangeal  joint,  the  middle  slip  is  in- 
serted into  the  base  of  the  second  phalanx,  while  the  two  lateral  are  continued 
onward  along  the  sides  of  the  second  phalanx  and  are  inserted  into  the  dorsal 
surface  of  the  last  phalanx.      (Plate  XXVI.) 

Action. — To  extend  the  fingers. 

Nerve  Suplpy. — Seventh  cervical  through  the  posterior  interosseous. 

Blood  Supply. — Posterior  interosseous. 

Extensor  minimi  digiti. — Description. — (Plate  XXXII.) — This  is  a 
slender  muscle  placed  on  the  inner  side  of  the  Extensor  communis  digitorum 
with  which  it  is  generally  connected.  Its  tendon  runs  through  a  separate 
compartment  in  the  annular  ligament  behind  the  inferior  radio-ulnar  joint, 
then  divides  into  two  as  it  crosses  the  hand,  the  outermost  division  being  joined 
by  the  slip  from  the  innermost  tendon  of  the  common  extensor.  The  two  slips 
thus  formed  spread  into  a  broad  aponeurosis  and  receive  a  slip  from  the  Ab- 
ductor minimi  digiti. 

Origin. — Common  tendon  by  a  thin  tendinous  slip  and  intermuscular 
septa.     (Plate  XXIII.) 

Insertion. — Second  ami  third  phalanges  of  the  little  finger.    (  Plate  XXVI.) 

Action. — Extends  the  little  finger. 

Nerve  Supply. — Seventh  cervical  through  the  posterior  interosseous. 

Blood  Supply. — Posterior  interosseous  and  radial. 

Anconeus. — Description. — This  is  a  small  triangular  muscle  placed  be- 
hind and  below  the  elbow-joint,  and  appears  to  be  a  continuation  of  the  external 
portion  of  the  Triceps.  Its  filters  diverge  from  their  origin,  the  upper  ones 
being  directed  transversely,  the  lower  obliquely  inward.      (Plate   XXXII.) 

Origin. — External  condyle  of  humerus   posteriorly.      (Plate  XXII.) 

Insertion.  —Side  of  olecranon  process  and  upper  fourth  of  posterior  sur- 
face of  shaft  of  ulna.     (Plate  XXIV.) 


8S  ANATOMY    IN    A    NUTSHELL. 

A.<  riON.     Extends  forearm. 

\i.i,\  i.  Supply.     Seventh  and  eighth  cervical  through  the  musculo-spiral, 

Blood  Supply.     Radial  and  superior  profunda. 


LESSON  XXI. 

Supinator  brevis. —  Description. — (Plate  XXXIII.) — This  is  a  broad  mus- 
cle of  hollow  cylindrical  form,  curved  round  the  upper  third  of  the  radius. 
It  consists  of  two  distinct  planes  of  muscular  fibers,  between  which  lies  the 
posterior  interosseous  nerve.  The  two  planes  arise  in  common.  The  fibers 
of  the  deeper  plane  form  a  sling-like  fasciculus,  which  encircles  the  neck  of 
the  radius  above  the  tuberosity.  Between  the  insertion  of  the  two  planes 
the  posterior  interosseous  nerve  lies  on  the  shaft  of  the  bone. 

Origin— The  superficial  plane  by  tendinous  and  the  deep  by  muscular 
fibers  from  tl)  the  external  condyle  of  the  humerus;  (2)  external  lateral  lig- 
ament of  elbow-joint;  (3)  orbicular  ligament  of  radius;  (4)  oblique  ridge  of 
ulna;  (5)  triangular  depression  in  front  of  the  ridge;  (6)  tendinous  expansion 
covering  the  surface  of  the  muscle.      (Plates  XXIII-XXIV.) 

Insertion.  The  superficial  fibers  into  the  outer  edge  of  the  bicipital 
tuberosity  and  oblique  line  of  the  radius;  the  deeper  fibers  into  the  posterior 
and  external  surface  of  the  shaft,  midway  between  the  oblique  line  and  head  of 
the  bone,  except  the  sling-like  fasciculous  which  is  attached  to  the  back  part  of 
the  inner  surface  of  the  radius.     (Plate  XXIV.) 

A.CTION.—  Stipulates   hand. 

Nerve  Supply.     Posterior  interosseous. 

Blood  Supply     Interosseous  and  radial  arteries. 

Extensor  ossis  metacarpi  pollicis. — Description. — (Plate  XXXIII). — This 
is  the  mosl  external  and  the  largest  of  the  deep  extensor  muscles.  It  lies  im- 
mediately below  the  supinator  brevis,  with  which  it  is  sometimes  united.  From 
its  origin  it  passes  obliquely  downward  and  outward  and  terminates  in  a 
tendon  which  runs  through  a  groove  on  the  outer  side  of  the  styloid  processof 
the  radius.  The  tendon  of  the  Extensor  brevis  pollicislies  in  the  samegroove. 
The  Extensor  pollicis  occasionally  gives  off  two  slips  near  its  insertion,  one 
to  the  trape/.ium.  and  the  other  to  blend  with  the  origin  of  the  Abductor 
pollicis. 

Origin.  From  outer  part  of  posterior  surface  of  shaft  of  ulna  below  in- 
sertion of  Anconeus,  from  the  interosseous  membrane,  and  from  the  middle 
third  of  the  posterior  surface  of  shafl  of  radius.     (Plate  XXIV.) 

Insertion.     Base  of  metacarpal  bone  of  thumb.     (Plate  XXVII.) 

Action.     Extends  thumb. 

Nerve  Si  pply.     Posterior  interosseous. 

Bl< Si  pply.     Posterior  interosseous. 

Extensor  brevis  pollicis.  Description.  (Plate  XXXIII.) — The  Exten- 
sor brevis  pollicis  (Extensor  primi  internodii  pollicis,)  the  smallest  muscle  of 
this  group,  lies  on  the  inner  side  of  the  preceding,  having  a  similar  direction 
and  passing  through  the  same  groove  on  tin1  outer  side  of  the  styloid    process. 


PLATE  XXXII 


tffc  !&) 


EXTENSOR  INCMCIS 


EXTENSOR  MINIM:  DIGIT! 


EXTENSOR  COMMUNIS  CIGlTORUM 


POSTERIOR    ANNULAR  LIGAMENT. 


ATTACHMENT     OF 
EXTENSOR  COMMUNIS  DIGITORUM 
TO     THIRI 


ATTACH  «J£I 
EXTENSOR  CO» 
TO     SEC 


s  /- 


V   J.  !    fl 


adductoh    i-ul 


EXTENSOR  MINIMI  DIGITI 


EXTENSOR   CARPI   ULNARIS. 


FLEXOR  CARPI  ULNARIS. 


EXTENSOR  BREVIS  POUICIS. 


-  EXTENSOR  CSSiS  METJCARP1  POLLiClS. 


EXTENSOR  CARPI   RSDIALIS  BREvlOR. 


EXTENSOR     COMMUNIS     QiGITORuM. 


EXTENSOR  CARPI  RAOIALIS  LONGIOR, 


SUPINATOR    LONGUS 


BRACHIALIS  ANIICUS. 


.  ,   '  it]  \       __  biceps. 

Muscles  of  the  Left  Forearm — Superficial  Layer— Posterior   \  iew 

89 


PLATE  XXXI 11 


-.'!•,   DR  MINIM    L'iG'T 


ABDUCTOR  MINIMI  DIGITI 


EXTENSOR  CARPI    ULNARIS. 


EXTENSOR  IND4CIS. 


RAOIAUS.EXTENSORS. 


FLEXOR  PROFUNDUS  OIGITOBUM 


FLEXOR  CARPI  ULNARIS 


ETtTENSOR  OSSIS  METACARPI  POLLICIS. 


SUPINATOR  BREVIS. 


EXTENSOR  CARPI  RAOIALIS  LONGIOR. 


-SUPINATOR    I  ONGUS 
BRACHIAUS  ANTICUS. 


Muscles  op  the  Left  Forearm — Deep  Layer — Postesior  View 

90 


ANATOMY    IX    A    NUTSHELL.  '.'1 

Origin. — Posterior  surface  of  shaft  of  radius,  below  Extensor  ossis  meta- 
carpi  pollicis  and  from  the  int<      --        -  membrane.     (Plate   XXH  . 

Insertion. — Base  of  first  phalanx  of  thumb.     (Plate  XW  1. 

Ai  tion. — Extends  the  proximal  phalanx  of  thumb. 

Xerye  Supply. — Seventh  cervical  through  the  posterior  inter  ss 

Blood  Supply. — Posterior  interosseous  artery. 

Extensor  longus  pollicis. — Description. — (Plate  XXXIII.)  —  The  Ex- 
tensor longus  pollicis  (Extensor  secundi  internodii  pollicis)  is  much  larger 
than  the  preceding  muscle,  the  origin  of  which  it  parti}'  covers  in.  It  termi- 
nates in  a  tendon  which  passes  through  a  separate  compartment  in  the  annu- 
lar ligament,  lying  in  a  narrow,  oblique  groove  at  the  back  part  of  the  lower  end 
of  the  radius.  It  then  crosses  obliquely  the  tendons  of  the  Extensor  carpi 
radialis  longior  and  brevior.  being  separated  from  the  other  extensor  tendons  of 
the  thumb  by  a  triangular  interval  in  which  the  radial  artery  is  found. 

Origin. — Outer  part  of  posterior  surface  of  shaft  of  ulna  distally  from 
origin  of  Extensor  ossi<  metacarpi  pollicis  and  from  interosseous  membrane. 
(Plate  XXIV.) 

Insertion.  —  Base  of  last  phalanx  of  thumb.     (Plate    XX\  I. 

Action. — Extends  thumb. 

Nerve  Supply. — Seventh  cervical  through  posterior  interosseous. 

Blood  Supply. — Posterior  interosseous  artery. 

Extensor  indicis. — Description. —  Plate  XXXIII.) — This  is  a  narrow, 
elongated  muscle  placed  on  the  inner  side  of.  and  parallel  with  the  preceding. 
Its  tendon  passes  with  the  Exten.-or  communis  digitorum  through  the  same 
canal  in  the  posterior  annular  ligament  and  subsequently  joins  the  tendon 
the  Extensor  communis  digitorum  which  belongs  to  the  index  finger,  opposite 
the  lower  end  of  the  corresponding  metacarpal  bone,  lying  to  the  ulnar  side  of 
the  tendon  from  the  common  extensor. 

Origin. — Shaft  of  ulna  posteriorly,  and  distally  from  Extensor  longus 
pollicis  and  from  interosseous  membrane.     (Plate  XXIV. 

Insertion. — Second   and  third  phalanges  of  index  finger  with  tendon 
common  extensor.      (Plate  XXVI.) 

A' tion. — Extends  index  ring 

Nerve   Supply. — Seventh  cervical  through  posterior  inter  ss 

Blood  Supply. — Posterior  inter  —        3  artery. 


LESSON   XXII. 

Radial  artery. — The  radial  artery  extends  from  the  bifurcation  of  thebrach- 
ial  and  ends  in  the  deep  palmar  arch.  It-  course  i-  shown  by  a  line  from  a 
point  about  half  an  inch  below  the  middle  of  the  bend  of  the  elbow  to  the  inner 
side  of  the  base  of  the  styloid  process  of  the  radius.  Tin-  artery  is  more  a  con- 
tinuation of  the  brachial  than  the  ulnar,  which  is  more  of  a  branch.  It  is  ac- 
companied by  venae  comites.  It-  branches  in  the  forearm  an-  radial  recurrent, 
muscular,  superficialis  volae,  and  anterior  carpal. 


ANATOMY    IX    A    NUTSHELL. 

The  radial  recurrent  arises  from  the  radial  just  below  the  elbow,  passes 
outward  between  the  Supinator  brevis  and  Supinator  longus,  also  separating 
the  radial  and  posterior  interosseous  uerves;  it  then  runs  towards  the  elbow 
between  the  Supinator  longus  and  the  Brachialis  anticus  to  supply  these  mus- 
cles  and  to  anastomose  with  the  anterior  terminal  branch  of  the  superior  pro- 
funda. 

The  muscular  branches  supply  the  muscles  on  the  radial  side  of  the  fore- 
arm. 

The  anterior  carpal  arises  near  the  lower  border  of  the  Pronator  quadratus; 
ii  passes  to  the  ulnar  side  ^\  the  forearm  under  the  tendons  to  anastomose  with 
anterior  carpal  of  ulnar,  thus  forming  the  loop  which  gives  branches  to  the 
wrist-joint. 

The  superficialis  volae  arises  from  the  artery  near  the  wrist  where  it  is 
about  to  wind  around  the  carpus.  It  passes  between  the  muscles  of  the  ball  of 
the  thumb,  sometime-  over  them.  It  anastomoses  with  the  ulnar,  completing 
the  superficial  palmar  arch.  The  pulse  may  often  be  felt  in  this  artery,  as 
well  a.-  in  the  radial,  when  it  arises  higher  than  usual. 

The  branches  in  the  wrist  are  the  posterior  carpal,  metacarpal  or  first  dor- 
sal interosseous,  dorsales  pollicis,  and  dorsalis  indicis.  After  the  radial  gives 
off  the  anterior  carpal  it  crosses  the  external  lateral  ligament  to  the  base  ofthe 
metarcapal  of  the  thumb,  lying  upon  the  scaphoid  and  trapezium.  In  this 
situation  it  is  crossed  by  the  three  extensors  of  the  thumb,  viz.,  Extensorossis 
metacarpi  pollicis  which  is  a  broad  muscle  and  comes  from  both  bones, 
the  Extensor  longus  pollicis  which  comes  from  the  long  bone  or  ulna,  and  the  Ex- 
tensor brevis  pollicis  which  comes  from  the  short  bone  or  radius.  It  then  passes 
between  the  two  heads  of  the  first  dorsal  interosseous  or  Abductor  indicis,  into 
tin'  palm.  It  passes  to  the  back  of  the  hand  for  two  reasons,  first  to  supply 
tin'  hack  of  the  hand  on  the  radial  side,  and  second  for  protection. 

The  posterior  carpal  arises  beneath  the  extensors  of  the  thumb,  passing 
beneath  the  extensor  tendon-  of  the  forearm  to  join  the  posterior  carpal  of  the 
ulnar,  making  the  posterior  carpal  arch.  It  uives  off  the  second  and  third  dor- 
sal interossei  which  pass  on  the  back  of  the  Third  and  Fourth  interossei  mus- 
cles to  the  metacarpophalangeal  joint  where  it  divides  into  digital  branches  to 
supply  the  contiguous  sides  of  the  middle,  ring,  and  little  fingers.  At  their 
proximal  extremity  they  receive  perforating  branches  from  the  deep  palmar 
arch.  At  the  distal  extremity  they  give  perforating  branches  to  the  digital 
branches  to  join   the  palmar  digital  arteries. 

The  metacarpal  or  first  dorsal  interosseous  may  conn'  from  the  posterior 
carpal,  bu1  it  generally  arises  from  the  radial.  It  passes  over  the  Second  dorsal 
interosseous  muscle  to  the  metacarpophalangeal  joint  where  it  is  divided  to 
supply  thr  contiguous  side-  of  the  index  and  middle  finders.  At  its  proximal 
extremity  it  receives  perforating  branches  from  the  deep  palmar  arch;  at  its 
distal  extremity  it  gives  branches  to  join  the  corresponding  digital  arteries. 
The  digital  arteries  end  at  the  firsl  interphalangeal  joint  where  they  join  the 
posterior  branch  of  the  collateral  digital  branches. 

The  dorsales  pollicis  are  two  in  number;  they  arise  from  the  radial  near 
the  base  of  the  first  metacarpal  bone  and  pass  along  the  sides  of  the  dorsum  of 
the  thumb. 


ANATOMY    IN    A    NUTSHELL. 


93 


The  dorsalis  indicis  arises  from  the  radial  just  before  it  passes  between  the 
two  heads  of  the  Abductor  indicis;  it  then  passes  over  the  dorsum  of  this  mus- 
cle, which  it  supplies,  to  the  radial  side  of  the  index  finger.  At  the  first  inter- 
phalangeal  joint  it  anastomoses  with  the  posterior  branch  of  the  radialis  in- 
dicis. 


PLATK  XXXIV 


THIRD  DORSAL  INTEROSSEOUS   lill-fij   SECOND  DORSAL   INTEROSSEOUS 

FIRST  DORSAL  INTEROSSEOUS 


FOURTH  DORSAL  INTEROSSEOUS 


The  Four  Dorsal  Enterossej 

The  deep  palmar  arch  is  formed  by  the  radial,  after  it  pusses  between  the 
two  heads  of  the  Abductor  indicis,  and  a  terminal  branch  of  the  ulnar.  This 
arch  has  its  convexity  distally;  it  lies  upon  the  bases  of  the  metacarpal  bones. 
It  has  five  branches,  four  from  the  convexity  and  one  from  the  concavity. 

The  princeps  polllcis   first    passes  between    the   Abductor  indicis  and   the 


94 


ANATOMY    IX    A    NUTSHELL. 


n-  •    ,     thP  distal  extremity  of  the  metacarpal  of  the  thumb 

ffhti«  i.  -I  from  the  convexity;  H  passes  along  the  ra<h£ 
,,,„.,'  /I",  palmar  surface  of  the  Index  finger,  at  firsl  it  passes  between  the 
Abductor  indicis  and  Adductor  polhcis. 

PLATE  XXXV 


SECOND  PALMAR  INTEROSSEOUS 


FIRST   PALMAR  INTEROSSEOUS 


THIRD  PALMAR  INTEROSSEOUS 


I'ii i:  Three  Palmar  [nterossei 

her.     They  pass  over  the  Second. 


The  palmar  Interossei  are  three  in  num 


T  ,,.    na  mar  muTO>M'i  an-   mihv    m   m. .......      „,    , 

Th J  anrTourth  palmar  Inter i    just  before  they  divide  mto  collateral 

,,■;:;,',  branches.     They  join  ,1 1 ling  digital  branches  of  the  super- 

^tSX^'i— ■  -  """"  ' '■■   They  pass  """""" 


ANATOMY    IN    A    NUTSHELL.  95 

two  heads  of  the  Three  inner  dorsal  interossei  to  join  the  dorsal  interosseous 

arteries. 

The  palmar  recurrent,  two  or  three,  pass  towards  the  wrist  and  join  the 
anterior  carpal  and  anterior  interosseous  t<>  supply  the  wrist-joint. 

Relations  of  the  Radial  Artery  in  the  Forearm. 

In  Front. — (1)  Skin.  (2)  Superficial  and  deep  fasciae,  3  Supinator 
Longus. 

Behind. — (1)  Tendon  of  Biceps,  (2)  Supinator  brevis,  (3)  Pronator  radii 
teres,  (4)  Flexor  sublimis  digitorum,  (5)  Flexor  longus  pollicis,  (6)  Pronator 
quadratus,  (7)  radius. 

Outp:r  Side. — (1)   Supinator  longus,  (2)  Radial  nerve  (middle  thir 

Inner  Side. — (1)   Pronator  radii  teres.  (2)   rdexor  carpi  radialis. 


LESSON  XXIII. 

Ulnar  artery. — The  ulnar  artery  is  a  branch  of  the  brachial  about  one-half 
an  inch  below  the  bend  of  the  elbow.  It  is  larger  than  the  raidal.  which  seems 
to  be  a  continuation  of  the  brachial  .  It  passes  over  the  anterior  annular  lig- 
ament on  the  radial  or  outer  side  of  the  pisiform  bone. 

The  anterior  ulnar  recurrent  arises  from  the  ulnar  just  below  its  origin. 
11  passes  towards  the  elbow  upon  the  Brachialis  anticus  and  under  the  Pro- 
nator radii  teres  to  the  front  of  the  internal  condyle  to  anastomose  with  the  an- 
terior branch  of  the  inferior  profunda  and  the  anastomotica  magna. 

The  posterior  ulnar  recurrent  is  the  larger  of  the  vessels  and  has  its  origin 
below  the  anterior.  It  passes  backward  and  inward  upon  the  Flexor  sublimis 
digitorum.  It  passes  between  the  two  heads  of  Flexor  carpi  ulnaris,  with  the 
ulnar  nerve,  to  the  back  of  the  internal  condyle  to  anastomose  with  the 
posterior  branch  of  the  inferior  profunda  and  the  anastomotica  magna. 

The  common  interosseous  is  the  next  in  order,  having  its  origin  opposite 
the  bicipital  tuberosity.  It  passes  upward  and  distally  to  the  beginning  of  the 
interosseous  membrane  where  it  divides  into  anterior  interosseous  and  pos- 
terior interosseous.     The  lumen  of  this  branch  is  the  largest  of  the  branches. 

The  anterior  interosseous  passes  to  the  distal  extremity  of  the  interosseous 
membrane  in  company  with  the  anterior  int<  -  nerve,  where  il  pass 

the  back  of  the  forearm.  It  has  venae  comites.  It  sends  a  branch  with  the 
median  nerve  called  the  median  artery  or  conn.-  nervi  mediani.  At  the  wrist  it 
anastomoses  with  the  anterior  carpal  artery  and  recurrent  branches  from  the 
deep  palmar  arch.  It  may  help  to  form  the  superficial  palmar  arch.  It  gives 
nutrient  branches  to  both  the  radius  and  ulna. 

The  posterior  nterosseous  artery  passesto  the  back  of  the  forearm  between 
the   oblique   ligamenl    and    inl  -    membrane.     It    passes   between    the 

Supinator  brevis  and  the  Extensor  ossis  metacarpi  pollicis,  then  lies  between 
the  two  layers  of  muscles  on  posterior  part  of  forearm  as  far  as  the  wrist.  It 
lies  internal  to  posterior  interosseous  nerve.  It  anastomoses  with  the  carpal 
of  radial  and  ulnar,  and  anterior  interosseous  arteries.  It  gives  off  the  posterior 
interosseous  recurrent  which  passes  under  the  Anconeus  to  the  interval  be- 
tween olecranon  and  external  condyle,  where  it  anastomoses  with  the  superior 
profunda,  the  anastomotica  magna  and  posterior  ulnar  recurrent. 

The  muscular  branches  vary  in  number  and  supply  the  adjacent  muscles. 


96  ANATOMY   IN   A   NUTSHELL. 

The  anterior  carpal  is  a  small  branch  which  has  itsorigin  at  the  distal  part 
of  the  ulnar  artery  near  the  anterior  annular  ligament.  It  passes  outward  to 
anastomose  with  the  anterior  carpal  of  the  radial.  These  two  arteries  make 
the  anterior  carpal  arch.  It  anastomoses  with  the  anterior  interosseous,  and 
recurrent  branches  from  the  deep  palmar  arch.  It  lies  beneath  the  tendons  of 
the   Flexor  profundus  digitorum. 

'The  posterior  carpal  arise-  a  little  proximally  of  the  pisiform  hone.  It 
passes  beneath  the  Extensor  carpi  ulnaris  to  the  hack  of  the  wrist  to  join  the 
posterior  carpal  of  the  radial  under  the  extensor  tendons. 

'The  superficial  palmar  arch  is  made  by  the  continuation  of  the  ulnar  in 
the  hand,  joining  the  superficialis  volae,  or  the  radialis  indicis,  or  the  princeps 
pollicis,  rarely  joining  a  large  median  artery. 

The  deep  ulnar  branch  passes  between  the  Abductor  minimi  digiti  and  the 
Flexor  brevis  minimi  digiti  to  make  the  deep  palmar  arch.  The  convexity  of 
the  superficial  palmar  arch  gives  four  digital  branches,  one  to  the  ulnar  side  and 
palmar  aspect  of  the  little  finger,  and  the  other  three  to  the  adjacent  sides  of 
the  little,  ring,  middle  and  index  fingers.  On  the  fingers  these  arteries  are  pos- 
terior to  the  nerves. 

Relations  of  the  Ulnar  Artery  in  the  Forearm. 

1\  Front.  Upper  half. — (1)  Superficial  layer  of  flexor  muscles.  (2)  Me- 
dian  nerve.     Lower  half — (3)   Superficial   fascia.    (4)  Deep  fascia. 

Behind. —  (1)   Brachialis  anticus,    (2)   Flexor   profundus  digitorum. 

Outer  Side.—  Flexor  sublimis  digitorum. 

Inner  Side.   -(1)   Flexor  carpi  ulnaris.  (2)  Ulnar  nerve  (lower  two-thirds.) 

Relations  of  the  Superficial   Palmar  Arch. 

1\    Front. — (1)  Skin.   (2)    Palmaris  brevis,   (3)   Palmar  fascia. 

Behind. — (1)  Annular  ligament,  (2)  Flexor  brevis  minimi  digiti,  (3) 
Superficial  flexor  tendons.  (4)   Divisions  of  median  and  ulnar  nerves. 


BRACHIAL  PLEXUS. 

LESSON  XXIV. 

A  plexus  is  a  net-work.  The  Brachial  Plexus  is  a  net-work  of  nerves  sit- 
uated in  the  axilla.  Its  branches  supply  the  upper  extremity.  It  is  called 
"brachial"  because  it  supplies  the  arm  or  brachium.  It  is  composed  of  the 
anterior  primary  branches  (Principle  IV  Lesson  III)  of  the  fifth,  sixth,  seventh, 
eighth  cervical  and  first  dorsal  nerves.  The  anterior  branches  of  the  fifth  and 
sixth  cervical  nerves  make  the  first  trunk.  The  anterior  branch  of  the  seventh 
cervical  nerve  makes  the  second  trunk.  The  anterior  branches  of  the  eighth 
cervical  nerve  and  part  of  the  first  dorsal  nerve  make  the  third  trunk.  These 
trunks  divide  into  anterior  and  posterior  branches  (secondary).  The  anterior 
branches  of  the  firsl  and  second  trunk  make  the  outer  cord;  the  anterior  branch 
of  the  third  trunk  make-  the  inner  cord;  and  the  posterior  branches  of  all  three 
trunks  make  the  posterior  cord.  They  are  called  outer,  inner,  and  posterior 
cords  of  the  brachial  plexus  <m  account  of  occupying  that  relation  to  the  second 
part  of  the  axillary  artery.     (Plates  VI-XVI-XVII.) 


PLATE  XXXVI 


Showing  the  Cutaneous  Nerve  Supply  of  the  Upper  Extremity 

97 


'.•s  ANATOMY    IN    A    NUTSHELL. 

The  axillary  artery  is  divided  into  three  parts  by  the  Pectoralis  minor 
muscle,  the  part  above  the  muscle  is  called  the  first  part,  the  part  behind  it  is 
called  the  second  part,  and  the  part  below  it  is  called  the  third  part.  A  branch 
from  the  outer  cord  joins  one  from  the  inner  cord  to  make  the  median  nerve. 
The  outer  cord  gives  off  the  external  anterior  thoracic  and  the  musculo-cutane- 
ous  nerves.  'The  inner  cord  gives  off  the  ulnar,  internal  cutaneous,  lesser  in- 
ternal cutaneous,  and  the  internal  anterior  thoracic  nerves.  The  posterior 
cord  gives  off  the  three  subscapular  and  divides  into  the  circumflex  and  musculo- 
spinal nerves.  The  musculo-spiral  divides  into  the  radial  and  posterior  inter- 
i  isseous. 

This  plexus  is  situated  in  the  posterior  triangle  of  the  neck  between  the 
Scalenus  anticus  and  the  Scalenus  medius,  being  covered  by  the  skin.  Platysma 
myoides,  and  deep  fascia;  the  posterior  belly  of  the  Omo-hyoid  and  the  trans- 
\  ersalis  colli  artery  cross  it.  It  next  lies  above  and  to  the  outer  side  of  thesub- 
clavian  artery:  it  passes  behind  the  clavicle  in  the  axilla  where  it  first  lies  to  the 
outer  side  of  the  first  portion  of  the  axillary  artery,  then  its  cords  lie  externally. 
internally,  and  posteriorly  to  the  second  part  of  the  axillary  artery.  From  the 
third  part  branches  are  given  to  the  upper  extremity. 

The  clavicle  divides  the  brachial  plexus  into  branches  above  it  and  branches 
below  it.  The  branches  above  are  communicating,  muscular,  posterior  thor- 
acic, and  suprascapular. 

The  communicating  branches  are.  (1)  one  from  the  fifth  cervical  or  from 
the  loop  between  the  fifth  and  sixth  cervical  to  the  phrenic,  which  union  takes 
place  on   the  Scalenus  anticus  muscle.      (2)    A  sympathetic  connection. 

The  muscular  branchesare,  (1  I  those  to  the  Longus  colli  whichcome  from 
the  fifth,  sixth,  seventh,  and  eighth  cervical  before  they  enter  into  the  brachial 
plexus.  (2)  Those  to  the  Scaleni  which  also  come  from  the  fifth,  sixth,  seventh, 
and  eighth  cervical  before  they  enter  into  the  brachial  plexus.  (3)  Those  to 
the  Rhomboidei,  which  come  from  the  fifth  cervical  and  pass  through  the 
Scalenus  medius  beneath  the  Levator  anguli  scapulae,  which  it  sometimessup- 
plies,  to  tiie  Rhomboidei.  (4)  The  nerve  to  the  Subclavius  which  comes  from 
the  fifth  and  sometimes  the  sixth  cervical.  It  often  communicates  with  the 
phrenic. 

The  posterior  thoracic  of  long  thoracic  (external  respiratory  of  Hell)  comes 
from  the  fifth,  sixth,  and  seventh  cervical.  It  is  formed  in  the  substance  of  the 
Scalenus  medius,  then  passes  behind  the  brachial  plexus  and  axillary  artery  to 
supply  the  digitations  of  the  Serratus  magnus. 

The  suprascapular  i-  formed  by  the  fifth  and  sixth:  it  passe>  beneath  the 
Trapezius  and  Omo-hyoid  to  pass  through  the  suprascapular  notch  into  the 
supraspinous  fossa  where  ii  gives  two  branches  to  the  Supraspinatus  muscle 
and  a  branch  to  the  shoulder-joint,  then  passes  around  the  greal  scapular  notch 
into  the  infraspinous  fossa,  giving  two  branches  to  the  Infraspinatus  muscle 
and  one  to  the  scapula  itself. 

All  the  other  branches  are  below  the  clavicle. 

The  external  or  superficial  anterior  thoracic  nerve  comes  from  the  outer 
cord  jusl  below  the  clavicle  and  it-  fibers  may  he  traced  to  the  fifth,  sixth,  and 


ANATOMY    IN    A    NUTSHELL.  99 

seventh  cervical  nerves.  It  passes  inward  across  the  axillary  vessels,  pierces 
the  costo-coracoid  membrane  and  supplies  the  Pectoralis  major.  It  commu- 
nicates with  the  internal  or  deep  anterior  thoracic.  This  loop  is  around  the 
front  and  inner  side  of  the  axillary  artery  and  branches  are  often  given  from  it 
to   the   Pectoralis   major. 

The  Internal  or  deep  anterior  thoracic  nerve  comes  from  the  inner  cord  and 
its  fibers  may  be  traced  to  the  eighth  cervical  and  first  dorsal  nerves.  It  passes 
between  the  axillary  artery  and  vein,  sometimes  piercing  the  sheath  of  the  vein. 
It  gives  a  filament  to  a  branch  from  the  external  or  superficial  anterior  thoracic 
then  pierces  the  costo-coracoid  membrane  to  supply  the  Pectoralis  minor;  after 
passing  through  the  substance  of  this  muscle  it    supplies  the   Pectoralis  major. 

The  subscapular  nerves  are  three  in  number,  the  upper,  the  middle,  and 
the  lower.  All  are  from  the  posterior  cord,  as  a  rule,  although  the  upper  one 
may  come  from  the  posterior  branch  of  the  first  trunk  before  it  enters  into  tin- 
posterior  cord.  The  upper  one  may  be  traced  to  the  fifth  and  sixth  cervical: 
it  supplies  the  Subscapulars  muscle. 

The  middle  or  long  subscapular  may  be  traced  to  the  seventh,  occasionally 
to  the  fifth  and  sixth;  it  supplies  the  Latissimus  dorsi.  The  lower  one  may  be 
traced  to  the  fifth  and  sixth  cervical  and  supplies  the  axillary  border  of  the  Sub- 
scapularis  and  the  'Feres  major.  The  Teres  major  may  be  supplied  by  a  separate 
branch. 

The  circumflex  comes  from  the  posterior  cord  in  common  with  the  musculo- 
spiral.  It  is  traced  to  the  fifth,  sixth,  and  seventh  cervical  nerves.  It  lies 
behind  the  third  portion  of  the  axillary  artery  where  it  passes  downward  and 
outward  to  the  lower  border  of  the  Subscapularis  muscle;  it  then  passes  through 
the  quadrilateral  space  with  the  posterior  circumflex  artery.  This  space  is 
hounded  above  by  the  Teres  minor,  below  by  the  Teres  major,  on  the  outside 
by  the  Humerus,  and  on  the  inside  by  the  long  head  of  the  Triceps.  It  gives 
an  articular  branch  to  the  shoulder-joint  which  pierces  the  capsular  ligament  : 
it  then  divides  into  a  superior  and  inferior  branch.  The  -ulterior  branch  winds 
around  the  surgical  neck  of  the  humerus  with  the  posterior  circumflex  vessels., 
along  the  Deltoid  to  its  anterior  border,  supplying  the  muscle  and  the  integu- 
ment over  its  lower  part.  The  inferior  branch  supplies  the  Deltoid  and  Teres 
minor.  The  part  supplying  the  Teres  minor  has  a  ganglion  upon  it.  It  then 
pierces  the  deep  fascia  to  supply  the  integument  on  the  lower  two-thirds  of  the 
posterior  surface  of  the  Deltoid  and  the  integument  over  the  long  head  of  the 
Triceps.  A  branch  from  the  circumflex  nerve  supplies  the  long  head  ol  the 
♦Biceps,  the  head  of  the  humerus  and  the  shoulder  joint. 

The  median  nerve  is  formed  by  a  branch  from  the  outer  cord  and  one  from 
the  inner  cord.  Its  fillers  may  be  traced  to  the  fifth,  sixth,  seventh  and  eighth 
cervical  and  first  dorsal  nerves.  This  junction  takes  place  a1  the  lower  border 
of  the  Teres  minor  as  a  rule,  although  it  may  be  almost  to  the  elbow-joint.  The 
branch  from  the  inner  cord  crosses  the  third  pari  of  the  axillary  artery;  the 
nerve  lies  then  to  the  outer  side  of  axillary  artery,  passing  to  the  distal  extremity 

of  the  arm  to  pass  between  the  two  heads  of  the  Pronator  radii  teres.  In  the 
axilla  it  lies  first  to  the  outer  side  of  the  third  part  of  the  axillary  artery,  in  the 

►When  the  long  head  ol  the  Biceps  slips  from  Its  normal  position  11  presses  on  this  nerve 
and  produces  pain — "Glass  .inn."    This  can  be  cured  osteopathlcally. 


PLATE  WWII 


DEEP     CERVICAL     NODE 


AXILLARY  NODES 


EPICONDYLAR    NODE     OR    GLAND 


MEDIAN    CEPHALIC 


Lymphatics  \m>   Veins  oi  the  Qppee   Extremity     Superficiai 

100 


ANATOMY    IN    A    NUTSHELL.  101 

arm  it  lies  to  the  side  of  the  brachial  artery  and  after  crossing  it  t<>  the  inner 
side  of  the  artery.  It  lias  no  branches  in  the  arm:  at  the  elbow  it  gives  off  two 
articular  branches  to  the  joint. 

After  passing  between  the  two  heads  of  the  Pronator  radii  teres  it  passes 
to  the  distal  extremity  of  the  forearm  where  it  passes  under  the  anterior  annular 
ligament.  In  its  course,  in  the  forearm.it  first  lies  between  the  Flexor  sublimis 
digitorum  ami  Flexor  profundus  digitorum,  then  between  the  tendon.-  of  the 
Flexor  sublimis  digitorum  and  Flexor  longus  pollicis.  It  supplies  all  the  mus- 
cles in  the  first  layer  of  the  forearm  except  the  Flexor  carpi  ulnaris.  which  are 
the  Pronator  radii  teres.  Flexor  carpi  radialis.  and  Palmaris  longus:  it  also  sup- 
plies the  one  muscle  in  the  second  layer  which  is  the  Flexor  sublimis  digitorum. 


LESSON  XXV. 

The  anterior  interosseous  nerve  is  given  off  just  below  and  is  accompanied 

by  the  anterior  interosseous  artery  to  the  distal  extremity  of  the  forearm  lying 
on  the  interosseous  membrane.  The  nerve  is  external  to  the  artery  being  be- 
tween the  Flexor  profundus  digitorum  and  Flexor  longus  pollicis.  This  branch 
supplies  the  Flexor  longus  pollicis,  Pronator  quadratus,  and  the  outer  side  of 
the  Flexor  profundus  digitorum.  It  send-  a  branch  to  the  wrist-joint,  also  one 
to  the  anterior  interosseous  artery  and  to  the  interosseous  membrane,  to  the 
medullar}-  arteries  and  to  the  periosteum  of  the  radius  and  ulna.  It  i>  worth 
while  to  note  that  the  anterior  interosseous  nerve  is  a  branch  from  the  median. 
and  the  posterior  Interosseous  nerve  is  a  branch  of  the  musculo-spiral  nerve, 
while  the  anterior  ami  posterior  interosseous  arteries  are  both  branches  of  the 
same  artery,  viz..  the  common  interosseous. 

The  palmar  cutaneous  branch  of  the  median  nerve  arises  in  the  distal  third 
of  the  forearm,  passes  between  the  Flexor  carpi  radialis  and  Palmaris  longus, 
pierces  the  deep  fascia  proximally  to  the  anterior  annular  ligament  and  passes 
over  that  ligament  to  the  integument  and  fascia  on  the  palmar  surface  of  the 
hand.  It  divides  into  two  divisions,  external  and  internal.  The  external  one 
supplies  the  skin  over  the  ball  of  the  thumb  ami  anastomoses  with  the  anterior 
cutaneous  branches  of  the  musculo-spiral  and  radial  nerves.  The  internal 
division  supplies  the  integumenl  on  the  palm,  except  that  on  the  ulnar  side  and 
anastomoses  with  the  palmar  cutaneous  branches  of  the  ulnar  nerve. 

The  median  nerve  then  enters  the  hand  beneath  the  anterior  annular  lig- 
ament. It  spreads  out  and  is  of  a  reddish  color.  It  divides  into  external  and 
internal  divisions.  It  lies  upon  the  flexor  tendons  and  is  covered  by  integu- 
ment, palmar  fascia,  and  the  superficial  palmar  arch.  The  external  division 
supplies  the  Abductor  pollicis.  Opponens  pollicis.  ami  superficial  head  ^\  the 
Flexor  brevis  pollicis.  and  occasionally  the  deep  head  of  that  muscle.  The 
other  muscles  of  the  thumb  are  supplied  by  the  ulnar.  It  then  divides  into 
first,  second,  and  third  digital  branches  for  the  thumb  and  index  finger.  The 
internal  division  gives  off  the  fourth  and  fifth  digital  branches  which  supply  the 
contiguous  sides  of  the  index  and  middle  fingers  and  the  middle  ami  ring  fi] 
then  there  are  five  digital  branches  from  the  median  nerve. 


L02  ANATOMY    IN    A    NUTSHELL. 

The  ulnar  nerve  arises  a  little  below  the  lower  border  of    the   Pectoralis 

minor,  from  the  inner  cord  of  the  brachial  plexus.  Its  fibers  may  be  traced  to 
the  eighth  cervical  and  firsl  dorsal.  It  lies  on  the  inner  side  of  the  axillary 
artery,  also  of  brachial  artery,  until  it  passes  below  the  insertion  of  the  Coraco- 
brachialis  where  it  forms  an  acute  angle,  and,  in  company  with  the  posterior 
branch  of  the  inferior  profunda  artery,  pierces  the  internal  intermuscular  septum, 
then  passing  down  to  the  groove  between  the  internal  condyle  and  the  ole- 
cranon process  it  gives  off  two  or  three  branches  to  the  elbow-joint,  then  passes 
between  the  two  heads  of  the  Flexor  carpi  ulnaris  in  company  with  the  pos- 
terior ulnar  recurrent  artery.  In  the  forearm  it  lies  between  the  Flexor  pro- 
fundus digitorum  ami  Flexor  carpi  ulnaris;  in  the  middle  third  of  the  forearm 
between  the  same  two  muscles  with  the  Flexor  sublimis  digitorum  on  the  other 
side.  It  is  situated  on  the  inner  side  of  the  ulnar  artery  and  crosses  the  anterior 
annular  ligament  on  the  radial  side  of  the  pisiform.  In  the  forearm  it  gives  off 
branches  near  the  elbow-joint  which  supply  the  Flexor  carpi  ulnaris  and  the 
inner  part  of  the  Flexor  profundus  digitorum. 

The  cutaneous  branches  arise  about  the  middle  of  the  forearm;  there  are 
two  of  these  branches.  The  one  most  superficial  pierces  the  deep  fascia  near 
the  wrist  to  supply  the  integument  and  anastomose  with  the  internal  cutane- 
ous. The  other  branch,  which  is  the  deeper  one,  is  called  the  palmar  cutane- 
ous. It  accompanies  the  ulnar  artery,  being  upon  its  anterior  surface,  to  the 
hand.  1  he  dorsal  cutaneous  arises  about  two  or  three  inches  from  the  wrist; 
it  passes  to  the  dorsal  aspect  of  the  wrist  under  the  Flexor  carpi  ulnaris,  super- 
ficial to  the  Extensor  carpi  ulnaris  to  supply  the  integument  on  the  ulnar  as- 
pect of  the  dorsum  of  the  hand  and  that  of  the  little  and  half  of  the  ring  fingers. 

The  superficial  terminal  or  palmar  branch  supplies  the  Palmaris  brevis, 
the  hypothenar  eminence,  the  inner  side  of  the  little  finger  on  its  volar  aspect, 
and  the  contiguous  sides  of  the  little  and  ring  fingers.  The  deep  palmar  arch 
or  branch  passes  between  the  Abductor  minimi  digiti  and  Flexor  brevis  minimi 
digiti.  then  through  the  Opponens  minimi  digiti  to  the  deep  surf  ace  of  the  flexor 
tendons  and  their  synovial  sheaths.  It  supplies  the  Abductor  minimi  digiti, 
Flexor  brevis  minimi  digiti.  opponens  minimi  digiti,  two  inner  Lumbricales, 
all  the  [nterossei,  Adductor  transversus  pollicis,  Adductor  obliqus  pollicis,  and 
inner  head  of  the  Flexor  brevis  pollicis  and  occasionally  the  outer  head. 

The   ulnar  nerve  SUppileS  eighteen    muscles. 

The  musculO-CUtaneOUS  or  external  cutaneous  (perforans  Casserii)  comes 
from  the  outer  cord  and  its  fibers  may  be  traced  to  the  fifth,  sixth,  and  seventh 
cervical  nerves.  It  supplies  muscles  in  the  arm  but  no  integument,  whereas  it 
supplies  integument  in  the  forearm  but  no  muscles.  It  begins  opposite  the 
lower  border  of  the  I Vctoralis  minor,  passing  outward  and  downward  to  pirece 
the  Coraco-brachialis  which  it  supplies.  It  divides  in  the  substance  of  this 
muscle  and  passes  to  the  outer  side  of  the  arm  between  the  Biceps  and  the 
Brachialis  amicus,  supplying  these  muscles.  It  sends  a  branch  with  the  nutri- 
ent artery  into  the  bone.  The  branch  to  the  Coraco-brachialis  is  given  off 
from  the  nerve  close  to  its  origin.  Occasionally  this  muscle  is  supplied  by  a 
separate   branch   from    the  outer  cord.      The   branch   to  the   Brachialis  amicus 


ANATOMY    IN    A    NUTSHELL. 


103 


sends  filaments  to  the  elbow-joint.     Near  the  outer  border  of  the  arm  and  a 

little  above  the  tendon  of  the  Biceps  the  nerve  pierces  the  deep  fascia,  anas- 
tomosing with  the  proximal  external  cutaneous  branch  of  the  musculo-spiral, 
passing  below  the  median  cephalic  vein  where  it  divides  into  anterior  and  pos- 
terior.    It  then  becomes  cutaneous. 

The  anterior  branch  passes  along  the  radial  side  of  the  forearm  to  supply 
the  integument  on  the  outer  half  of  the  anterior  surface,  ending  in  the  thenar 
eminence.     It  anastomoses  with  the  radial  and  the  palmar  cutaneous  branch  of 


PLAT 

i 


OBLIQUE.  LIGAMENT 


POST.  LIGAMENT 


The  Elbow-Joint — External  View 

the  median.     It  gives  off  an  articular  branch  to  the  carpal  bones  which  pierces 
the  deep  fascia  to  pass  with  the  radial  artery  to  the  back  of  the  wrist. 

The  posterior  branch  is  smaller  than  the  anterior  one.  It  passes  along  the 
posterior  aspect  on  the  radial  side  of  the  forearm  to  the  wrist.  It  anastomoses 
with  the  radial  and  the  distal  external  cutaneous  of  the  musculo-spiral. 


LESSON   XXVI. 

The  musculo-spiral  is  the  largest  branch  of  the  brachial  plexus.  It  mid  the 
circumflex  are  the  terminal  branches  of  the  posterior  cord.  It  supplies  mus- 
cles and  integument  both  above  and  below  the  elbow .      Its  libers  may  be  traced 


104 


ANATOMY    IX    A    NUTSHELL. 


to  the  fifth,  sixth,  seventh,  and  eighth  cervica]  nerves  and  the  first  dorsal  nerve. 
It  commences  a1  the  lower  border  of  the  Pectoralis  major.  It  first  lies  behind 
the  third  part  of  the  axillary  artery  in  front  of  the  Subscapulars.  Teres  major, 
and  Latissimus  dorsi.  After  leaving  the  axilla  it  lies  on  the  inner  side  of  the 
upper  one-third  of  the  humerus  behind  the  brachial  artery  and  in  front  of  the 
long  head  of  the  'Triceps,  li  passes  between  the  two  humeral  heads  of  the 
Triceps  in  the  musculo-spiraJ  groove  in  company  with  the  superior  profunda 
artery.  This  nerve  and  the  anterior  branch  of  the  superior  profunda  artery 
perforate  the  externa!  intermuscular  septum  and  pass  in  the  groove  between 
the  Supinator  longus  and  Extensor  carpi  radialis  longior  on  the  outer  side,  and 

PLATE   XXXIX 


8'ceps 

T£ND0N 


,'0BLlQUt 


UGAMElur 


0AB/CUUfi 
L'GAMEHT         J" 


The  Elbow-Joint — Internal  View 


the  Brachialis  anticus  on  the  inner  side.  In  the  lower  part  of  this  gr00V<  it 
divides  into  the  posterior  interosseous  and  radial  nerves.  The  musculo-spiral 
nerve  supplies  five  muscles  vi/...  Supinator  longus,  Extensor  carpi  radialis 
longior,  Triceps,  Brachialis  anticus  and  Anconeus.  If  we  substitute  Anconeus 
for  heboid  we  will  have  the  live  muscles  attached  to  the  external  intermus- 
cular septum.  This  nerve  has  muscular  branches  (just  given),  an  articular 
branch,  cutaneous  branches  and  two  terminal  branches,  viz.,  posterior  interos- 
seous and  radial. 


ANATOMY    IN    A    NUTSHELL.  105 

Its  articular  branch  is  given  off  from  one  of  the  branches  to  the  Supinator 
longus,  Extensor  carpi  radians  longior,  or  Brachialis  anticus  to  the  elbow-joint. 
Its  cutaneous  branches  supply  the  integumenl  of  the  arm  over  the  musculo- 
spiral  groove;  in  the  forearm  over  the  radial  aspect  of  the  dorsum  of  the  forearm 
as  far  as  the  wrist.  The  internal  cutaneous  branch  given  off  in  the  axilla  crosses 
the  tendon  of  the  Latissimus  dorsi,  then  passes  behind  the  intercosto-humeral 
nerve,  pierces  the  dee])  fascia  to  supply  the  integument  on  the  middle  of  the 
back  of  the  arm  nearly  to  the  olecranon.  Ii  gives  off  its  upper  and  lower  ex- 
ternal cutaneous  before  it  pierces  the  external  intermuscular  septum;  the  upper 
one  perforates  the  outer  head  of  the  Triceps,  accompanies  the  cephalic  vein  to 
the  elbow  and  supplies  the  integument  over  the  lower  half  of  the  outer  and  inner 
aspect  of  the  arm.  The  lower  one  is  the  larger.  It  arises  behind  the  external 
condyle  to  simply  the  integument  on  the  lower  part  of  the  arm  and  radial  as- 
pect of  posterior  surface  of  forearm  as  far  as  the  wrist.  It  anastomoses  with 
the  musculo-spiral  and  internal  cutaneous. 

The  radial  nerve  is  the  smaller  of  the  two  terminal  branches  of  the  musculo- 
spiral  and  is  purely  cutaneous.  It  runs  towards  the  wrist  under  the  Supinator 
longus.  It  passes  in  front  of  the  elbow. radial  recurrent  a.,  and  Supinator  bre  vis. 
In  the  middle  third  of  the  forearm  it  lies  parallel  to.  and  on  the  outer  side  of. 
the  radial  artery,  superficial  to  the  Pronator  radii  teres  muscle.  The  nerve 
turns  backward  beneath  the  tendon  of  the  Supinator  longus  and  becomes  cu- 
taneous by  piercing  the  deep  fascia  of  the  outer  side  of  the  forearm  about  three 
inches  from  its  distal  extremity:  here  it  divides  into  two  branches,  external 
and  internal.  The  externa!  one  supplies  the  integument  on  ball  and  outer 
border  of  thumb,  anastomosing  with  the  musculo-cutaneous.  The  inner  one 
anastomoses  with  the  musculo-cutaneous  and  dorsal  branch  of  the  ulnar,  sup- 
plying integument  on  the  dorsum  of  the  hand  and  fingers  in  a  manner  somewhat 
similar  to  that  of  the  median  nerve  on  the  palmar  surface,  the  first  branch  to 
the  inner  side  of  the  thumb,  the  second  to  the  radial  side  of  the  index  finger, 
the  third  to  the  adjacent  sides  of  the  index  and  middle  fingers,  and  the  fourth 
to  the  adjacent  sides  of  the  middle  and  ring  fingers. 

The  posterior-interovseous  nerve  passes  around  the  outer  side  of  the  prox- 
imal end  of  the  radius,  through  the  substance  of  the  Supinator  brevis  to  the 
back  of  the  forearm,  then  passe>  between  the  superficial  and  deep  layers  to 
about  the  middle  of  the  forearm  where  it  passes  beneath  the  Extensor  longus 
pollicis  to  lie  on  the  interosseous  membrane  on  which  it  passes  almosl  to  the 
wrisl  in  company  with  the  posterior  interosseous  artery.  At  the  the  distal  ex- 
tremity it  accompanies  the  terminal  branch  of  the  anterior  interosseous  artery. 
It  then  passes  through  the  rourth  opening  of  the  posterior  annular  ligament  to 
the  back  of  the  wrist  where  it  has  a  ganglion  upon  it.  from  which  are  given  oft 
its  branches  of  distribution  to  the  wrist-joint  and  carpal  joint.-.  It  supplies  all 
the  muscles  on  the  back  of  the  forearm  excepl  the  Anconeus.  It  supplies  nine 
muscles  in  all.  viz.,  Extensor  communis  digitorum,  Extensor  minimi  digiti, 
Extensor  carpi  ulnaris,  Supinator  brevis,  Extensor  ossis  metacarpi  pollicis, 
Extensor  longus  pollicis,  Extensor  brevis  pollicis,  Extensor  indicis,  all  ol  which 


106  ANATOMY    IN    A    NUTSHELL. 

are  on  the  back  of  the  forearm,  and  Extensor  carpi  radialis  brevior  in  the  radial 
region. 

The  internal  cutaneous  nerve  comes  from  the  inner  cord  and  its  fibers  may 
be  traced  to  the  eighth  cervical  and  first  dorsal  nerves.  The  cutaneous  branch 
perforates  the  deep  fascia  in  the  axilla  to  supply  integument  over  the  back  of 
the  arm  nearly  to  the  elbow.  About  half  way  along  the  inner  side  of  the  arm 
it  pierces  the  deep  fascia  with  the  basilic  vein,  dividing  into  anterior  and  pos- 
terior branches.  The  anterior  branch  passes  to  the  forearm  either  in  front  of, 
or  behind  the  median  basilic  vein,  supplies  integument  of  the  ulnar  aspect  of  the 
anterior  surface  of  the  forearm  as  far  as  the  wrist  and  communicates  with  the 
ulnar.  The  posterior  branch  passes  in  front  of  the  internal  condyle  to  the 
forearm  where  it  supplies  integument  on  the  ulnar  aspect  of  the  dorsum  of  the 
forearm  as  far  as  the  wrist.  Above  the  elbow  it  anastomoses  with  the  lesser 
internal  cutaneous  and  at  the  wrist  with  the  dorsal  cutaneous  of  the  ulnar. 

The  lesser  internal  cutaneous  (nerve  of  Wrisberg)  is  the  smallest  branch  of 
the  brachial  plexus.  It  comes  from  the  inner  cord  and  its  fibers  are  traced  to 
the  first  dorsal  and  sometimes  the  eight  cervical  in  addition.  In  the  axilla  it 
communicates  with  the  intercosto-humeral  forming  one  or  two  loops.  It  is  sit- 
uated on  the  inner  side  of  the  axillary  often  being  separated  from  the  vein  by 
the  ulnar  nerve.  About  the  middle  of  the  arm  it  pierces  the  dee]>  fascia  supply- 
ing integument  over  the  olecranon. 


LESSON  XXVII. 

The  hand.— (Plates  XXVI-XXVII.) — There  are  twenty-seven  bones  in 
the  hand  while  there  are  but  twenty-six  in  the  foot,  there  being  one  more  bone 
in  the  carpus  (wrist )  than  in  the  tarsus  (ankle.)  The  number  of  muscles  in  the 
hand  is  twenty,  the  same  as  in  the  foot.  There  are  also  twenty  muscles  in  the 
forearm.  In  the  thumb  (thenar  eminence)  there  are  five  muscles,  viz.,  Ab- 
ductor pollicis,  <  >pponens  pollicis  (  Flexorossis  metacarpi  pollicis.)  Flexor  brevis 
pollicis,  Adductor  obliquus  pollicis,  and  Adductor  transversus  pollicis.  The  first 
two  gel  the  median  nerve,  the  third  one  gets  both  the  median  and  the  ulnar 
nerves,  while  the  last  two  get  the  ulnar.  On  the  ulnar  side  of  the  hand  there  is 
the  Palmaris  brevis  and  the  three  muscles  of  the  little  finger  (hypothenar  emi- 
nence!, viz..  A  lull  ict  or  minimi  digit  i.  Flexor  brevis  minimi  digiti,  and  theOpponens 
minimi  digiti  (Flexor  ossis  metacarpi  minimi  digiti).  All  these  are  supplied  by 
the  ulnar  nerve.  In  the  middle  palmar  legion  there  are  four  Lumbricales, f our 
Dorsal  interossei,  and  three  Palmar  interossei.  The  two  outer  Lumbricales  are 
supplied  by  the  median  nerve,  and  the  two  inner  ones  and  the  seven  Interossei 
by  the  ulnar  nerve.  The  bones  in  the  carpus  are  in  two  rows,  those  of  the  first 
row.  beginning  on  the  radial  side  are  the  scaphoid,  semilunar,  cuneiform,  and 
pisiform,  and  those  in  the  second  row  beginning  on  the  radial  side  are  the  trape- 
zium, trapezoid,  os  magnum,  and  unciform.  The  five  beyond  the  carpus  are 
called  the  metacarpals,  and  the  fourteen  in  the  fingers  and  thumb  are  the  phal- 
langes.  Then  the  eighl  carpal,  plus  the  five  metacarpal,  plus  the  fourteen 
phalanges,  make  the  twenty-seven  bones  of  the  hand. 


ANATOMY    IN    A    NUTSHELL. 


107 


The  scaphoid  ossifies  the  sixth  year.  It  articulates  with  five  bones,  viz.. 
radius  proximally.  trapezium  and  trapezoid  distallv.  and  os  magnum  and  semi- 
lunar internally.  It  has  one  muscle  attached,  the  Abductor  pollicis.  The 
blood  supply  of  the  carpal  bones  is  the  anterior  and  posterior  carpal  arch,  and 
a  large  branch  from  the  anterior  interosseous,  and  small  branches  from  the  pos- 
terior interosseous. 

The  semilunar  ossifies  the  fourth  year.  It  articulates  with  five  bones,  viz.. 
radius  proximally.  os  magnum  and  unciform  distallv.  scaphoid  and  cuneiform 


CAPSULAR  LIGAMENT 


INT.  LATERAL  LISA!  -1ENT \\\    X  .-XP0\]^2i^A*l1'^\        It',' 


POST.  RADIO-ULNAR  LIGAMENT 


EXT.  LATERAL  LIGAMENT. 


Tin:  Wrist-Joint — Posterior   View 


on  either  side.  It  has  no  muscle  attached.  The  blood  supply  i-  the  same  as 
the  carpus. 

The  cuneiform  ossifies  the  third  year.  It  articulates  with  three  bone-. 
viz.,  semilunar  externally,  pisiform  in  front,  and  unciform  distally,  and  with 
the  triangular  interarticular  fibro-cartilage  which  separates  it  from  the  distal 
end  of  the  ulna.     There  are  no  muscles  attached  to  this  bone. 

The  pisiform  ossifies  the  twelfth  year.  It  articulates  with  one  bone,  the 
cuneiform.  It  has  two  muscles  attached.  Flexor  carpi  ulnaris  and  Abductor 
minimi  diuiti. 


108 


ANATOMY    IN    A    NUTSHELL. 


The  trapezium  ossifies  the  fifth  year,  and  articulates  with  four  bones,  viz., 
scaphoid  proximally,  trapezoid  and  second  metacarpal  internally,  and  the  first 
metacarpal  distally.  It  has  three  muscles  attached,  Abductor  pollicis,  Flexor 
brevis  pollicis,  Flexor  ossis  metacarpi  pollicis.  and  occasionally  the  Extensor 
ossis    metacarpi    pollicis. 

'The  trapezoid  ossifies  the  eighth  year.  It  articulates  with  four  hones,  the 
scaphoid  proximally,  second  metacarpal  distally,  trapezium  externally,  and  the 
os  magnum  internally.  It  may  have  a  few  fibers  of  the  Adductor  obliquus 
pollicis  attached. 

PLATE  XLI 


CAPSULAR  LIGAMENT 


EXTERNAL  LATERAL  LIGAMEN1 


Tiii:  Wrist-Joint — Anterior  View 


The  OS  magnum  ossifies  the  first  year.  It  articulates  with  seven  bones, 
scaphoid  and  semilunar  proximally,  second,  third,  and  fourth  metacarpal  dis- 
tally,  trapezoid  on  the  radial  side,  and  the  unciform  on  the  ulnar  side.  It  has 
one  muscle   attached,   the   Adductor  obliquus  pollicis. 

The  unciform  ossifies  the  second  year.  It  articulates  with  five  bones,  semi- 
lunar proximally,  the  fourth  and  fifth  metacarpal  distally,  the  cuneiform  inter- 
nally and  the  os  magnum  externally.     It  has  three  muscles  attached,  Flexor 


ANATOMY    IN    A    NUTSHELL.  109 

carpi  ulnaris,  Flexor  ossis  metacarpi  minimi  digiti,  and  Flexor  brevis  minimi 
digiti. 

Metacarpal  bones. —  (Plate  VII.) — Each  one  has  two  centers,  one  for  the 
shaft  and  one  for  the  distal  extremity,  except  the  metacarpal  of  the  thumb  and 
it  has  one  for  the  proximal  extremity.  The  nucleus  for  the  shaft  appears  about 
the  eighth  or  tenth  week  of  intrauterine  life,  and  that  for  the  diaphysis  the  third 
year,  uniting  with  the  shaft  about  the  twentieth  year.  Each  phalanx  has  two 
centers,  one  for  the  shaft  "which appears  the  eighth  or  tenth  week,  and  one  for 
the  epiphysis  between  the  third  and  fifth  year, and  joins  the  shaft  the  eighteenth 
year.  The  epiphysis  for  each  phalanx  is  proximal,  so  the  nutrient  artery  runs 
towards  the  distal  end  (Principle  III,  Lesson  I).  The  center  for  the  distal  phalanx 
is  at  the  distal  extremity  of  the  shaft,  while  that  for  the  other  phalanges  is  at 
the  center  of  the  shaft.  The  metacarpal  of  the  thumb  articulates  with  two 
bones,  viz..  trapezium  proximally.  and  the  first  phalanx  of  the  thumb  distally. 
It  has  four  muscles  attached,  Extensor  ossis  metacarpi  pollicis,  Flexor  ossis 
metacarpi  pollicis,  Flexor  brevis  pollicis,  and  the  First  dorsal  interosseous.  The 
second  metacarpal  articulates  with  five  bones,  the  trapezium,  trapezoid,  and  os 
magnum  proximally,  the  third  metacarpal  internally,  and  the  first  phalanx  of 
the  index  finger  distally.  It  has  six  muscles  attached,  the  First  and  Second 
dorsal  interossei.  Extensor  carpi  radialis  longior  on  the  dorsal  aspect  of  the  bone 
and  the  Extensor  carpi  radialis,  First  palmar  interosseous,  and  the  Adductor 
obliquus  pollicis  on  the  palmar  aspect  of  the  bone.  The  third  metacarpal  artic- 
ticulates  with  four  bones,  os  magnum  proximally,  the  second  metacarpal  ex- 
ternally, the  fourth  metacarpal  internally,  and  the  first  phalanx  of  the  middle 
finger  distally.  It  has  six  muscles  attached;  on  the  dorsal  aspect  the  Second 
and  Third  dorsal  interossei,  and  the  Extensor  carpi  radialis  brevior  and  on 
the  palmar  aspect  the  Adductor  transversus  pollicis.  Adductor  obliquus  pollicis, 
and  Flexor  carpi  radialis.  The  fourth  metacarpal  articulates  with  five  bones. 
os  magnum  and  unciform  proximally,  os  magnum  and  third  metacarpal  exter- 
nally, the  fifth  metacarpal  internally  and  the  first  phalanx  of  the  ring  finger 
distally.  It  has  three  muscles  attached;  on  the  dorsal  aspect  the  Third  and 
Fourth  dorsal  interossei,  and  on  the  palmar  aspect  the  Second  palmar  inter- 
osseous. The  fifth  metacarpal  articulates  with  three  hones,  the  unciform  prox- 
imally, the  unciform  and  fourth  metacarpal  externally,  and  the  lirst  phalanx 
of  the  little  finger  distally.  It  has  five  muscles  attached;  the  Extensor  carpi 
ulnaris,  Plexor  carpi  ulnaris,  Third  palmar  Interosseous,  Fourth  dorsal  inter- 
osseous, and  Plexor  ossis  metacarpi  minimi  digiti. 

Flood  supply  of  the  first  metacarpal  bone  is  derived  from  the  princeps 
pollicis  artery;  it  enters  on  the  ulnar  side,  and  is  directed  towards  the  head 
of  the    hone. 

For  the  second  metacarpal  bone,  the  nutrient  artery  P  derived  from 
lirsl  palmar  interosseous.  It  enters  on  the  ulnar  side,  and  is  directed  towards 
the  proximal  end  or   base   of  the  bone. 

For  the  third  metacarpal  hone  ih<  nutrient  artery  is  derived  from  the 
interosseous;  il  enters  as  a  rule,  on  the  radial  side  and  is  directed  towards 
the  base. 


110  ANATOMY    IX    A    NUTSHELL. 

For  the  fourth  metacarpal  bone  the  nutrient  artery  is  furnished  by  the 
second  interosseous;  it  enters  on  radial  side  of  shaft,  and  is  directed  towards 
the  proximal  end. 

For  the  fifth  metacarpal  bone  the  nutrient  artery  is  derived  from  the 
third  interosseous;  it  enters  the  shaft  on  the  radial  side,  and  is  directed  to- 
wards  the  proximal  end.      (Plate  VI 1 .   page  33.) 


LESSON   XXVIII. 

The  first  phalanx  of  the  thumb  articulates  with  two  bones,  the  metacarpal 
of  the  thumb  proximally,  and  the  second  phalanx  distally.  It  has  five  muscles 
attached,  the  Al idiictor  pollicis,  Adductor  obliquus,  Adductor  transversus 
pollicis.  Extensor  brevis  pollicis.  and  the  Flexor  brevis  pollicis.  The  second, 
or  Last  phalanx  of  the  thumb  articulates  with  one  bone,  the  first  phalanx  of  the 
thumb.  It  has  two  muscles  attached,  the  Extensor  longus  pollicis  and  the 
flexor  longus  pollicis. 

The  first  phalanx  of  the  index  finger  articulates  with  two  bones  the  second 
metacarpal  proximally.  and  the  second  phalanx  of  the  index  finger  distally.  It 
has  two  muscles  attached,  the  First  dorsal  interosseous,  and  the  First  palmar  in- 
terosseous. The  second  phalanx  of  the  index  finger  articulates  with  two  bones, 
the  first  phalanx  proximally,  and  the  third  phalanx  distally.  It  has  three 
muscles  attached,  the  Extensor  communis  digitorum  Extensor  indicis.  and  the 
flexor  sublimis  digitorum.  The  last  phalanx  of  the  index  finger  articulates 
with  one  bone,  the  second  phalanx  proximally.  It  has  three  muscles  attached, 
the  Extensor  communis  digitorum,  Extensor  indicis.  and  Flexor  profundus 
digitorum.  The  first  phalanx  of  the  middle  finger  articulates  with  two  hones, 
the  metacarpal  of  the  middle  finger  proximally.  and  the  second  phalanx  of  the 
middle  finger  distally.  It  has  two  muscles  attached,  the  Second  and  Third 
dorsal  interossei.  The  second  phalanx  of  the  middle  finger  articulates  with 
two  bones,  the  first  phalanx  proximally.  and  the  third  phalanx  distally.  In  has 
two  muscles  attached,  the  Extensor  communis  digitorum  and  Flexor  sublimis 
digitorum.  The  third  phalanx  articulates  with  one  hone,  the  second  phalanx 
proximally.  It  has  two  muscles  attached,  the  Extensor  communis  digitorum 
and    flexor  profundus  digitorum. 

The  lir>t  phalanx  of  the  ring  finger  articulates  with  two  bones,  the  fourth 
metacarpal  proximally.  and  the  second  phalanx  of  the  ring  finger  distally.  It 
ha-  two  muscles  attached,  the  Fourthdorsal  interosseous  and  the  Third  palmar 
interosseous.  The  second  phalanx  of  the  ring  finger  articulates  with  two  bones. 
the  first  phalanx  of  the  ring  finger  proximally,  and  the  third  phalanx  distally. 
It  has  two  muscles  attached,  the  Extensor  communis  digitorum  and  Flexor 
sublimis  digitorum.  The  third  phalanx  of  the  ring  finger  articulates  with  one 
hone,  the  second  phalanx  proximally.  and  has  two  muscles  attached,  the  Ex- 
tensor communis  digitorum  ami  flexor  profundus  digitorum. 

The  first  phalanx  of  the  little  finger  articulates  with  two  bones,  the  fifth 
metacarpal  proximally.  and  the  second  phalanx  of  the  little  finger  distally.  It 
ha-  three  muscles  attached,  the  Extensorbrevis  minimi  dieiti,  Abductor  minimi 


ANATOMY    IN    A    NUTSHELL. 


Ill 


digiti,  and  the  Third  palmar  interosseous.  Thesecond  phalanx  of  the  little 
finger  articulates  with  two  hones,  the  first  phalanx  proximally  and  the  third 
phalanx  distally.  It  has  three  muscles  attached,  the  Extensor  communis 
digitorum.  Extensor  minimi  digiti,  and  Flexor  sublimis  digitorum.  The  third 
phalanx  of  the  little  finger  articulates  with  one  hone,  the  second  phalanx  prox- 
imally, and  has  three  muscles  attached,  the  Extensor  communis  digitorum 
Extensor  minimi  digiti.  and  Flexor  profundus  digitorum. 

Abductor    pollicis. —  Description.  —  (Plate    XXXI.)-  This   is   a    thin    flat 
muscle  placed  immediately    beneath  the  integument.      It   passes  outward  and 

PLATE   XLII 


Showing  the  Synovial  Membranes  of  the  Wrist 


downward  and  terminates  in  a  flat   tendon,  sending  a  slip  to  join  the  tendon  of 
the  Extensor  longus  pollicis. 

ORIGIN.  —  Ridge  of  trapezium  and  annular  ligament.      (Plate  XXVII.) 

Insertion.-   Radial  side  at  base  of  first  phalanx  of  thumb.  (Plate  XXVII.) 

Action.—  Abducts  the  thumb. 

Nerve  Supply.     Sixth  cervical  through  the  median. 


112  ANATOMY   IN   A   NUTSHELL. 

Blood  Supply.     From  superficialis  volae  artery. 

Opponent  pollicis. ■■-(  Flexor  ossis  metacarpi  pollieis.) — Description. — 
(Plate  XXXI.)     This  is  a  small  triangular  muscle  placed  beneath  the  preceding. 

Origin.— (Plate  XXVI.)— Palmar  surface  of  trapezium  and  annular 
ligament. 

I  nsertii  in.  Whole  length  of  metacarpal  of  thumb  on  radial  side.  (Plate 
XXVI. 

Action.     Flexes  metacarpal  of  thumb. 

Nerve  Supply.     Sixth  cervical  through  the  median. 

Blood  Supply.     From  radial  and  superficialis  volse  arteries. 

Flexor  brevis  pollicis.  Description. — (Plate  XXXI.) — This  muscle  con- 
sists of  two  portions  outer  and  inner,  having  separate  origins  and  insertions. 
The  outer  portion  is  the  more  superficial  and  has  a  sesamoid  hone  developed  in 
its  tendon.     The  inner  and  deeper  portion  is  very  small. 

Origin.-  (Outer  portion)  Trapezium  and  outer  two-thirds  of  annular  lig- 
ament.    ( Inner  portion)  Ulnar  side  of  first  metacarpal  bone.    (Plate  XXVIII.) 

Insertion.  —  Both  sides  of  base  of  first  phalanx  of  thumb  by  two  tendons. 
(Plate  XXVII.) 

Action.-  Flexes  thumb. 

Nerve  Supply. — Outer  portion,  sixth  cervical  through  median;  inner 
portion,   eighth   cervical   through   ulnar. 

Blood  Supply. — From  radial  artery. 

Adductor  obliquus  pollicis. — Description. — (Plate  XXXI.) — This  muscle 
arises  by  several  slips.  The  greater  number  of  fillers  pass  obliquely  downward 
and  converge  to  a  tendon  which  mutes  with  the  tendons  of  the  deeper  portion 
of  the  flexor  brevis  and  Adductor  transversus  pollicis,  a  sesamoid  bone  being 
developed  in  the  tendon  of  insertion.  A  considerable  fasciculus  passes  ob- 
liquely outward  beneath  the  tendon  of  the  long  flexors  to  join  the  superficial 
portion  of  the  short  flexor  and  the  Abductor  pollicis.  This  muscle  was  formerly 
described  as  the  deep  portion  of  the  Flexor  brevis  pollicis. 

Origin.— (1)  Os  magnum;  (2)  bases  of  second  and  third  metacarpal 
bones;  (3)  anterior  carpal  ligaments;  (4)  sheath  of  tendon  of  Flexor  carpi 
radialis.     (Plate  XXVII.) 

Insertion.-  Inner  side  of  base  of  first  phalanx  of  thumb.   (Plate  XXVII.) 

Action.      Moves  thumb  inward  toward  index  finger. 

Nerve  Supply.     Eighth  cervical  through  ulnar. 

Blood  Supply.-  From  the  palmar  arches. 

Adductor  transversus  pollicis.  Description.  —  (Plate  XXXI.) — This  is 
the  mosl  deeply  seated  of  tins  group  of  muscles;  it  is  triangular  in  form,  arising 
by  its  broad  base.  The  libers  converge  toward  their  insertion  which  is  in  com- 
mon with  the  inner  part  of  the  Flexor  brevis  pollicis  and  the  Adductor  obliquus 
pollicis.  From  this  common  tendon  a  slip  is  prolonged  to  the  Extensor  longus 
pollicis. 

Origin.  bower  tw<  -thirds  of  metacarpal  of  middle  finger  on  palmar  sur- 
face.    (Plate   XXVII.) 

Insertion.  Ulnar  side  of  base  of  firsl  phalanx  of  thumb  by  common  ten- 
don.      (Plate    XXVU    i 


ANATOMY    IN    A    NUTSHELL.  113 


Action. — Draws  thumb  towards  median  line. 
Xerye  Supply. — Eighth  cervical  through  ulnar. 
Blood  Supply. — From  the  palmar  arches. 


LESSOX  XXIX. 

Palmaris  brevis. — Description. — (Plate  XXXI.) — This  is  a  thin,  quad- 
rilateral muscle  placed  beneath  the  integument  on  the  ulnar  side  of  the  hand. 
The  palmar  fascia  is  in  relation  with  its  deep  surface  and  separates  it  from  the 
ulnar  vessels  and  nerve. 

Origin. — Annular  ligament  by  tendinous  fasciculi  and  palmar  fascia. 

Insertion. — Skin  on  inner  border  of  palm.     (Plate  XXXI.) 

Action. — Corrugates  skin  of  hand. 

Xera'e  Supply. — Eighth  cervical  through  the  ulnar. 

Blood  Supply. — The  ulnar  artery. 

Abductor  minimi  digiti. — Description. — (Plate  XXXI.) — This  muscle  is 
situa  ted  on  the  ulnar  border  of  the  palm  of  the  hand. 

Origin. — Pisiform  bone  and  from  the  tendon  of  the  Flexor  carpi  ulnaris. 

Insertion. — By  two  slips,  the  one  into  ulnar  side  of  base  of  first  phalanx 
of  little  finger:  the  other  into  ulnar  border  of  the  aponeurosis  of  the  Extensor 
minimi  digiti.     (Plate  XXVII.) 

Action. — Abducts  little  finger  from  middle  line  of  hand. 

Xerye  Supply. — Eighth  cervical  through  the  ulnar. 

Blood  Supply. — The  ulnar  artery. 

Flexor  brevis  minimi  digiti. — Description. — (Plate  XXXI-XXVII.) — The 
Flexor  brevis  minimi  digiti  lies  on  the  same  plane  as  the  preceding  muscle,  on 
its  radial  side.  It  is  separated  from  the  Abductor  at  its  origin  by  the  deep 
branches  of  the  ulnar  artery  and  nerve.  This  muscle  is  sometimes  wanting; 
the  Abductor  is  then  usually  of  large  size. 

Origin. — From  the  convex  aspect  of  the  hook  of  the  unciform  bone  and 
anterior  surface  of  annular  ligament. 

Insertion. — Inner  side  of  base  of  first  phalanx  of  little  finger. 

Action. — Flexes  little  finger. 

Nerve  Supply. — Eighth  cervical  through  the  ulnar. 

Blood  Supply. — The  ulnar  artery. 

Opponens  minimi  digiti  (Flexor  ossis  metacarpi  minimi  digiti). — Descrip- 
tion.— (Plate  XXXI.) — This  is  a  triangular  muscle  placed  immediately 
beneath  the   preceding   . 

Origin. — From  convexity  of  hook  of  unciform  bone  and  contiguous  por- 
tion of  annular  ligament.      (Plate   XXVII.) 

Insertion. — Whole  length  of  metacarpal  of  Little  finger  along  ulnar  mar- 
gin.    (Plate   XXVII.) 

Action. — Draws  fifth  metacarpal  forward  so  as  to  deepen  hollow  of  palm. 

Nerve  Supply. — Eighth  cervical  through  ulnar. 

Blood  Supply. — Ulnar  artery. 

Lumbrieales. — Description. — (Plate  XXXI) — The  Lumbricales  are  four 
small  fleshy  fasciculi,  accessories  to  the  deep  Flexor  muscle. 


1    14 


ANATOMY  IN   A   NUTSHELL. 


Origin.     Tendons  of  deep  flexor.    (Plate  XXXI.) 

[nsertion.-  Tendinous  expansion  from  Extensor  communis  digitorum  on 
hack  of  each  finger. 

\i  i  ion.     To  flex  firsl   phalanges. 

Nerve  Si  pply.  The  two  outer  Lumbricales  by  the  sixth  cervical 
through  the  third  and  fourth  digital  branches  of  the  median;  the  two  inner  by 
the  eighth  cervical  through  deep  palmar  branch  of  ulnar.  The  third  lnm- 
brical  receives  the  median  in  almost  half  the  cases. 

Blood  Si  pply.— From  digital  branches  of  the  superficial  palmar  arch 
and  the  interosseous  branches  of  the  deep  palmar  arch. 

Dorsal  Interossei.  —  Description.  —  ( 1  dates  |  XXXI Y-XXX  [II.)  —These 
small  muscles,  four  in  number,  occupy  the  intervals  between  the  metacarpal 
bones.  They  are  bipenniform.  Between  the  double  origin  of  each  is  a  narrow 
triangular  interval,  through  the  firsl  of  which  passes  the  radial  artery;  through 
each  of  the  miter  three  passes  a  perforating  branch  from  the  deep  palmar  arch. 

The  Abductor  indicis  or  the  Firsl  dorsal  interosseous  is  the  largest  of  these 
muscles. 

Origin. — by  two  heads;  (1)  Outer  head  from  upper  half  of  ulnar  border 
of  first  metacarpal  hone.  ('_')  Inner  head  from  almost  the  whole  length  of  the 
radial  border  of  the  second  metacarpal  bone.      (Plate  XXVI.) 

Insertion.     Into  the  radial  side  of  base  of  first  phalanx  of  index  finger. 

'The  Second  dorsal  interosseous. 

Origin.  By  two  heads  from  the  adjacent  sides  of  the  second  and  third 
metacarpal.      (  Plate  XXVI. J 

Insertion  into  the  radial  side  of  the  first  phalanx  of  middle  finger. 

The  Third  dorsal  interosseous. 

ORIGIN.  By  two  heads  from  the  adjacent  sides  of  the  third  and  fourth  meta- 
carpal bones.     (Plate  XXVI.) 

Insertion.  -Into  the  ulnar  side  of  the  firsl   phalanx  of  middle  finger. 

The   Fourth  dorsal  interosseous. 

Origin.  By  two  heads  from  the  adjacent  sides  of  the  fourth  and  fifth  meta- 
carpal bones.     (Plate  XXVI.) 

Insertion.     Into  the  ulnar  side  of  the  first  phalanx  of  ring  finger. 

Action.  (1)  Extend  the  last  two  phalanges.  (2)  Flex  the  metacarpo- 
phalangeal joints,  (3)   Ahdnct  the  fingers. 

Blood  Supply.     From  deep  palmar  and  posterior  carpal  arches. 

Nerve  Supply.     Deep  branches  of  the  ulnar  nerve. 

The  Palmar  interossei  which  are  placed  on  the  palmar  surface  of  the  sec- 
ond. Fourth  and  fifth  metacarpal  bones  are  three  in  number.  Their  insertion 
besides  being  into  the  bone  is  into  the  aponeurotic  expansion  ^(  the  common 
tendon  of  the  same  finger,  the  same  as  the  dorsal  interossei.     (Plate  XXXV.) 

Firsl  palmar  interosseous. 

Origin.      By  one  head  from  the  ulnar  side  of  the  second  metacarpal  hone. 

Insertion.     Into  the  ulnar  side  of  the  firsl  phalanx  of  index  finger. 

Second  palmar  interosseous. 

<  >RIGIN.      By  one  head  from  the  radial  side  of  the  fourth  metacarpal    hone 


ANATOMY    IN    A    NUTSHELL.  115 

Insertion. — Into  the  radial  side  of  the  first  phalanx  of  ring  finger. 
Third  palmar  interosseous. 

Origin. — By  one  head  from  the  radial  side  of  the  fifth  metacarpal  bone. 
Insertion. — Into  the  radial  side  of  the  first  phalanx  of  little  finger. 
Each  finger  has  two  [nterossei  muscles  except  the  little  finger.     The  Ab- 
ductor minimi  digiti  takes  the  place  of  one  of  the  pair. 
Nerve  Supply. — Ulnar. 
Blood  Supply. — Deep  palmar  arch. 
Action. — Same  as  the  Dorsal  interossei,bu1  these  adduct  instead  of  abduct. 


LKSSOX   XXX. 

Fascia  of  the  arm. — Just  beneath  the  skin  is  the  superficial  fascia  which 
has  two  layers,  a  superficial  one  consisting  mainly  of  adipose  tissue,  and  a  deep 
one  which  is  fibrous  in  structure  and  is  in  contact  with  the  deep  fascia.  The 
superficial  nerves;  vessels  and  lymphatics  lie  between  these  two  layers. 

The  deep  fascia  of  the  arm  forms  a  sleeve  which  encloses  the  muscles  and 
most  of  the  vessels  and  nerves.  It  is  continuous  with  the  fascia  of  the  chest. 
back,  shoulder  above  by  being  attached  to  the  clavicle,  the  scapula  ami  the 
spine,  and  to  that  of  the  forearm  by  being  attached  to  the  condyles  of  the  hu- 
merus and  olecranon  of  the  ulna.  It  is  thin  over  the  Biceps,  thick  over  the 
Triceps;  strengthened  on  the  inner  side  by  fibers  from  the  tendon  of  the  Pec- 
toralis  major  and  Latissimus  dorsi,  on  the  outer  side  by  fiber-  from  the  tendon 
of  the  Deltoid;  the  axillary  fascia  is  also  continuous  with  it.  The  external  in- 
termuscular septum  extending  from  the  insertion  of  the  Deltoid  to  the  External 
condyle  and  attached  to  the  superior  condylar  ridge  joins  the  inner  surface  of 
the  deep  fascia,  thus  dividing  the  sleeve  or  cylinder  of  fascia  into  an  anterior 
and  posterior  compartment,  the  anterior  one  having  flexor  muscles  in  it  and  the 
the  posterior  one  extensor  muscle.-.  This  septum  is  pierced  by  the  musculo- 
spiral  nerve  and  superior  profunda  artery  from  behind  forward.  It  has  five 
muscles  attached  to  it,  viz..  Deltoid,  Brachialis  anticus,  Triceps.  Supinator 
longus,  and  Extensor  carpi  radialis  longior.  In  these  five  muscles  if  we  sub- 
stitute the  Deltoid  for  Anconeus  we  will  have  the  five  muscles  supplied  by  the 
musculo-spiral   nerve. 

The  internal  intermuscular  septum  i-  thicker  than  the  external  one:  it 
extends  from  the  insertion  of  the  Coraco-brachialis  to  the  internal  condyle  ^\ 
the  humerus,  being  attached  to  the  supracondylar  ridge  to  the  inner  surface  of 
the  sleeve  of  fascia  of  the  forearm.  It  also  divides  the  muscles  into  an  anterior 
and  posterior  division.  Il  has  three  muscles  attached  to  ii.  vi/...  the  Triceps, 
Brachialis  anticus,  and  Coraco-brachialis,  and  occasionally  the  Pronator  radii 
teres.  If  we  stubsitute  the  Triceps  for  Biceps  in  this  group  of  muscles  we  will 
have  the  muscles  supplied  by  the  niusculo-cutaneotis  nerve.  The  basilic  vein 
pierces  the  deep  fascia  at  the  junction  n\'  the  lower  third  with  the  middle  third 
of   the   humerus. 

The  deep  fascia  of  the  forearm  is  continuous  with  thai  of  the  arm  at  the 
elbow  and  with  that   of  the  hand  ;it  the  wrist.      It  passes  over  the  anterior  an- 


lit)  ANATOMY    IN    A    NUTSHELL. 

nular  ligament  which  is  in  reality  the  aponeurosis  which  separates  the  first  and 
second  layers  of  the  muscles  of  the  forearm.  It  passes  from  the  pisiform  bone 
and  unciform  process  to  the  scaphoid  and  trapezium;  it  is  a  strong  fibrous  band. 
At  the  posterior  aspect  it  is  thickest  where  it  is  attached  to  the  sides  of  the 
triangluar  posterior  surface  of  the  olecranon  and  to  all  of  the  posterior  ridge  of 
the  ulna.  It  receives  a  band  from  the  bicipital  fascia  below  the  internal  con- 
dyle in  front,  and  an  aponeurosis  from  the  insertion  of  the  Triceps  behind.  It 
is  pierced  by  a  communicating  vein  at  the  cubital  fossa. 

The  posterior  annular  ligament  is  strengthened  by  transverse  fibers  and 
passes  from  the  outer  border  of  the  lower  end  of  the  radius  across  to  the  inner 
side  of  the  pisiform  and  cuneiform  bones,  its  inner  surface  being  attached  to  the 
ridge  on  the  posterior  surface  of  the  radius.  It  makes  six  canals  for  the  passage 
(if  the  extensor  tendons;  the  first  canal  has  the  Extensor  ossis  metacarpi  pol- 
licis  and  Extensor  brevis  pollicis;  the  second  the  Extensor  carpi  radialis  longior 
and  Extensor  carpi  radialis  brevior;  the  third  the  Extensor  longus  pollicis;  the 
fourth  the  Extensor  communis  digitorum,  which  is  in  the  superficial  layer, 
and  the  Extensor  indicis,  which  is  in  the  deep  layer;  the  fifth,  the  Extensor 
minimi  digiti  which  is  in  the  superficial  layer;  the  sixth,  the  Extensor  carpi 
ulnaris  which,  is  in  the  superficial  layer. 

The  anterior  annular  ligament  has  nine  muscles  attached  to  it,  all  those  of 
the  thumb  except  the  Adductor  transv<  rsus  pollicis,  and  all  those  of  the  little 
finger  except  the  Abductor  minimi  digiti;  then  there  are  four  of  the  thumb 
and  two  of  the  little  finger, making  six  ;  besides  these  six  it  has  the  Flexor  carpi 
ulnaris,  Palmaris  longus, and  Palmaris  brevis, making  the  nine.  The  tendon  of 
i  he  Flexor  carpi  radialis  pierces  the  anterior  annular  ligament  and  the  Palmaris 
Longus  passes  over  it.  but  is  also  attached  to  it.  The  median  nerve  and  the 
tendon-  of  three  muscles  pass  under  it;  the  muscles  are  the  Flexor  sublimis 
digitorum,   flexor  profundus  digitorum,  and  Flexor  longus  pollicis. 

Fascia  of  the  hand. — The  fascia  on  the  back  of  thehand  isthinand  is  com- 
posed mostly  of  transverse  fibers.  This  fascia  is  a  continuation  of  the  posterior 
annular  ligament.  It  connects  the  extensor  tendons  together  on  the  back  of  the 
hand.  Between  the  fingers  it  dips  down  to  join  the  web  which  connects 
the  bases  of  the  fingers.  The  deep  layer  is  attached  to  the  back  of  the  meta- 
carpal.- and  covers  the  Dorsal  intemssei. 

Palmar  Fascia.  The  deep  palmar  fascia  consists  of  strong  fibrous  tissue 
covering  the  palmar  surface  of  the  hand.  It  is  for  the  most  part  formed  by  the 
expansion  of  the  tendons  of  the  Palmaris  longus.  It  is  also  continuous  with 
the  anterior  annular  ligamenl  proximally.  It  has  a  central  and  two  lateral 
portions.  The  central  portion  is  triangular  with  the  apex  towards  the  wrist 
and  base  towards  the  fingers.  The  superficial  part  is  formed  by  longitudinal 
filier-  and  the  deep  part  bytransverse  fibers.  Its  base  is  divided  into  four  pro- 
cesses wh'n  h  j<  in  the  ligamenta  vaginalis  of  the  finger  tendons.  (Plates  XXIX- 
XX  XI  o 

Ligamenta  vaginalis  are  fibrous  -heaths  or  theca  over  the  flexor  tendons. 
They  are  so  attached  to  the  phalanges  as  to  form  osseo-aponeurotic  canals 
These  -heaths  are  strong  opposite  the  middle  of  the  first  and  second  phalanges, 


ANATOMY    IN    A    NUTSHELL.  117 

but  much  thinner  opposite  the  joints.  Each  sheath  is  lined  by  a  synovial  mem- 
brane, which  is  reflected  upon  the  tendons.  The  synovial  sheaths  for  the  ten- 
dons of  the  thumb  and  little  finger  are  continuous  with  the  two  synovial  bursa' 
beneath  the  anterior  annular  ligament,  but  those  for  the  intervening  digits 
terminate  in  a  sac  near  the  metacarpophalangeal  articulation.  The  outer  por- 
tion (thenar  fascia)  covers  the  ball  of  the  thumb.  Proximally  it  is  attached  to 
the  anterior  annular  ligament,  the  tendons  of  the  Palmaris  brevis  and  apo- 
neurosis from  the  tendons  of  the  Extensor  ossis  metacarpi  pollicis.  It  contin- 
ues distally  with  the  ligamenta  vaginalia  of  the  Flexor  longus  pollicis.  The  inner 
portion  or  hypothenar  fascia,  is  triangular  with  the  apex  proximally  and  at- 
tached to  the  anterior  annular  ligament  and  deep  fascia  of  the  forearm  at  the 
inner  side  of  the  wrist :  distally  it  is  covered  above  by  the  Palmaris  brevis. 
(Plate  XXX.) 


LESSON  XXXI. 

Besides  the  arterial,  venous  and  capillary  circulation  there  is  a  lymphatic 
circulation  extending  over  the  body  by  beginning  in  microscopical  spaces  and 
extending  until  they  form  lymphatic  vessels.  These  vessels  are  enlarged  by 
receiving  radicles  or  tributaries  in  a  like  manner  to  the  veins.  Along  the  course 
of  the  lymphatic  vessels  are  lymphatic  nodes,  sometimes  called  glands.  There 
are  in  the  neighborhood  of  seven  hundred  of  these  nodes.  They  are  situated 
principally  in  the  abdominal  and  thoracic  cavities.  In  the  upper  extremity 
they  are  found  no  farther  than  the  elbow.  In  the  lower  extremity  they  are 
found  no  farther  than  the  popliteal  space,  as  a  rule:  however,  a  few  may  be 
found  on  the  anterior  tibial  artery.  These  nodes  manufacture  the  white  blood 
corpuscles.  There  are  four  other  places  in  the  body  where  they  are  manu- 
factured.viz.. spleen,  thymus  gland,  thyroid  gland  and  the  red  marrow  of  b 

The  lymph  of  all  the  body,  except  the  right  side  of  the  head,  the  right  side 
of  the  thorax,  the  right  arm,  and  the  upper  surface  of  the  liver  collects  into  a 
large  duct,  the  left  lymphatic  or  thoracic  duct.  It  is  called  thoracic  duct  be- 
cause it  passes  through  the  thorax.  It  is  about  fifteen  or  eighteen  inches  long. 
It  begins  in  front  of  the  second  lumbar  vertebra  where  it  is  enlarged  (recep- 
taculum  chyli)  and  extends  through  the  thorax,  through  the  superior  opening 
of  the  thorax,  and  empties  into  the  left  subclavian  or  innominate  vein. 

The  heart  is  the  main  factor  in  the  circulation  of  the  lymph.  The  other 
factors  will  be  learned  in  physiology.  The  lymphatic  vessels  and  nodes,  like 
the  veins  of  the  arm,  are  in  two  sets,  a  superficial  and  deep  set.  After  the  blood 
has  passed  through  the  arteries  and  capillaries,  nourishing  the  various  parts,  it 
comes  back  by  means  of  the  vein.-. 

The  superficial  veins  of  the  distal  extremity  receive  the  name  radial,  an- 
terior and  posterior  ulnar,  and  median.  They  lie  between  the  two  layers  of 
the  superficial  fascia.      (Plate  XXXVII.) 

The  anterior  ulnar  is  formed  by  a  network  of  veins  at  the  anterior  and  ulnar 
side  of  the  hand  and  wrist.  It  extends  on  this  aspect  of  the  forearm  t<>  the 
bend  of  the  elbow  where  it  joins  the  posterior  ulnar  to  form  the  common  ulnar. 


lis 


ANATOMY    IN    A    NUTSHELL. 


The  posterior  ulnar  begins  a1  the  ulnar  aspecl  of  the  wrist,  from  which  it 
passes  to  the  bend  of  the  elbow  to  join  the  anterior  ulnar. 

The  common  ulnar  runs  upward  and  outward  to  join  the  median  basilic  to 
form  the  basilic,  which  pierces  the  deep  fascia  in  the  inner  side  and  below  the 
middle  of  the  forearm  to  ascend  with  the  brachial  artery  and  continues  as  the 
axillary  vein.  At  times  the  common  ulnar  is  absent,  the  anterior  and  posterior 
ulnar  joining  the  median  basilic  separately. 

The  median  vein  is  formed  on  the  palmar  surface  of  the  hand  and  passes  to 
the  bend  of  the  elbow  where  it  divides  into  two  branches,  median  basilic  and 
median  cephalic.  It  communicates  with  the  venae  comites  of  the  ulnar  be- 
fore it  reaches  the  elbow.  This  communicating  link  is  called  the  deep  median 
vein. 

The  radial  begins  on  the  dorsum  of  the  thumb  and  radial  aspect  of  the  hand; 
ii  passes  to  the  elbow-joint  where  it  joins  the  median  cephalic  forming  the 
cephalic. 

The  cephalic  vein  passes  on  the  outer  side  of  the  Biceps  to  the  groove  be- 
tween the  Heboid  and  the  Pectoralis  major;  it  perforates  the  deep  fascia  and 
the  costo-coracoid  membrane  to  end  in  the  axillary  vein  below  the  clavicle.  It 
occasionally  connects  with  the  external  jugular  or  subclavian  by  a  branch  in 
front  of  the  clavicle  called  the  jugular  cephalic. 

The  deep  veins  of  the  upper  extremity  accompany  the  arteries;  they  are 
called  venae  comites  and  are  connected  along  their  course  by  transverse  branches. 
The  digital  arteries  have  venae  comites  which  unite  at  the  base  of  the  fingers  to 
end  in  venae  comites  of  the  superficial  palmar  arch.  Those  of  the  radial  side 
accompany  the  superficialis  volae,while  those  of  the  ulnar  side  end  in  the  deep 
ulnar  veins.  The  veme  comites  of  the  ulnar  and  radial  unite  to  form  the 
brachial  venae  comites.  The  venae  comites  of  the  anterior  and  posterior  inter- 
osseous unite  at  the  proximal  extremity  of  the  forearm,  ending  in  the  ulnar 
venae  comites.  The  deep  palmar  veme  comites  empty  into  the  radial  externally 
and  the  ulnar  internally.  The  brachial  veme  comites  are  formed  by  those  of 
the  forearm;  they  accompany  the  artery  and  empty  into  the  axillary  just  above 
the  lower  border  of  the  tendon  of  the  Latissimus  dorsi. 

The  axillary  vein  is  a  continuation  of  the  basilic.  It  accompanies  the  axil- 
lary artery  and  becomes  the  subclavian  vein  at  the  upper  extremity  of  the  axilla. 
It  has  a  pair  of  valves  opposite  the  lower  border  of  the  Subscapularis.  It 
receives  radicles  corresponding  to  the  branches  of  the  axillary  artery.  It  also 
receives  the  cephalic  vein. 


ANATOMY    IN    A    NUTSHELL.  119 

The  axilla  is  the  anatomical  space  through  which  passes  the  brachial  plexus 
and  the  axillary  vessels.  It  is  filled  with  lymphatic  vessels  and  nodes  and  areo- 
lar tissue.  It  is  pyramidal  in  shape,having  four  sides,  a  base. and  an  apex.  The 
apex  corresponds  to  a  point  between  the  clavicle,  the  upper  part  of  the  scapula 
and  the  first  rib.  The  base  is  the  arm-pit  which  is  made  by  fascia  passing  from 
the  lower  borders  of  the  Latissimus  dorsi  behind  and  the  Pectoraiis  major  in 
front.  The  anterior  margin  of  the  base  is  higher  than  the  posterior  margin. 
This  space  is  narrow  externally,  but  broad  internally. 

Its  boundaries  are  as  follows:     Plate  XVI. 

In  Front: — (1)   Pectoraiis  major.  (2)    Pectoraiis  minor. 

Behind: — (1)  Subscapulars  (above,)  (2)  Teres  major  and  (3)  Latissimus 
dorsi  (below.) 

Outer  Side: — (1)  Humerus,    2)  Biceps,  (3)  Coraco-brachialis. 

Ennek  Side: — (1)  First  four  ribs  and  their  intercostal  spaces.  (2)  a  part  of 
the  Serratus  magnus. 

The  axillary  vessels,  brachial  plexus,  branches  of  the  intercostal  nerves, 
lymphatic  nodes,  all  connected  by  areolar  tissue  and  fat  lie  in  this  space. 

In  finishing  the  arm  it  is  well  to  review  the  cutaneous  nerve  supply  of  the 
hand  which  is  as  follows:     Plate  XXXVI. 

All  the  integument  on  the  ulnar  side  of  the  middle  line  of  the  ring  finger  on 
both  palmar  and  dorsal  surfaces  of  the  hand  is  supplied  by  the  ulnar  nerve. 
This  line  on  the  dorsum  of  the  hand  may  be  drawn  through  the  middle 

OF  THE  MIDDLE  FINGER  INSTEAD  OF  THE  RING  FINGER.       All  (ill  the  radial  side  of 

this  line  on  palmar  surface  is  supplied  by  the  median,  on  the  dorsal  surface  by 
the  radial.  The  radial  nerve  extends  to  the  base  of  the  thumb  nail,  to  the  distal 
interphalangeal  joint  of  index  finger  and  not  quite  to  the  proximal  interphal- 
angeal  joint  of  middle  finger,  and  sends  a  few  twigs  to  the  skin  of  the  metapha- 
langeal  articulation  of  ring  finger.  The  parts  of  the  dorsal  of  the  thumb,  index. 
middle  and  ring  fingers  not  supplied  by  the  radial  get  the  median. 

The  synovial  membrane  of  the  wrist  (Plate  XLII.)  This  membrane  con- 
sists of  five  portions.  First  portion  is  called  membrana  sacciformis  and  is 
between  the  interarticular  fibro-cartilage  and  the  ulna,  also  extending  between 
the  radius  and  ulna.  The  second  portiox  is  between  the  radius  and  inter- 
articular fibro-cartilage  proximally  and  the  scaphoid,  semilunar  and  cuneiform 
distally.  The  third  portion  is  between  the  trapezium  and  metacarpal  nl  the 
thumb.  The  fourth  portion  is  large  and  extends  between  the  scaphoid, 
semilunar  and  cuneiform  proximally  and  after  sending  septa  between  the  bones 
of  the  second  row  of  the  wrist  ends  by  separating  this  second  row  from  the  sec- 
ond, third,  fourth  and  fifth  metacarpal  bones  distally.  It  also  sends  projec- 
tions between  the  metacarpal  bones  just  mentioned.  Tim:  fifth  PORTION  is 
between  the  cuneiform  and  pisiform  bones. 


120  ANATOMY    IN    A    NUTSHELL. 


REVIEW  QUESTIONS. 

1.  I  trim.-  Anatomy. 

2.  Define  each  of  its  nine  divisions. 

:;.  ( rive  three  definitions  for  Aponeurosis. 

I.  What   IS  a  tendon? 

.",.  Give  two  definitions  for  Sinus, 

ft.  Define  Apophysis 

7.  Define  Epiphysis. 

8.  Which  way  do  the  nutrient  arteries  run  in  the  bones  of  the  arm? 
!t.  Which  way  do  the  nutrient  arteries  run  in  the  bones  of  the  leg? 

10.  ( rive  four  rules  tor  Epiphysis. 
ll.i  rive  functions  of  Periosteum. 

12.    How  does  a  long  hone  grow  in  length,  also  in  thickness? 
L3.   Name  the  ninety  long  hones. 

11.  Name  the  forty  flat  horn-. 

1.").   Name  the  forty  irregular  bones, 
lfi.    Name  the  thirty  short  bones. 

1 7.  Name  eight  eminences  on  bones. 

18.  Name  fourteen  prominences  on  bones. 

19.  Name  five  articular  cavities  in  bones. 

l'ii.  Name  ten  non-articular  cavities  in  bones. 

21.  Name  the  bones  of  the  body  and  tell  what  each  means. 

22.  Now  many  muscles  in  the  body? 

23.  Name  six  ways  in  which  muscles  take  their  names. 
2  1.  What  is  the  origin  of  a  muscle? 

25.  Whal  is  the  insertion  of  a  muscle? 

26.  Give  parts  thai  make  a  joint. 

27.  <  rive  Hilton's  law. 

28.  '  uve  all  subdivisions  of  synarthrosis  and  an  example  of  each. 

29.  Same  of  A.MPHIARTHROSIS. 

30.  Same  of  DIARTHROSIS. 

31.  How  do  ligaments  take  their  names? 

32.  What  is  a  muscular  nerve? 
.",:;.   What  is  a  cutaneous  nerve? 

34.  What  is  a  musculo-cutaneous  nerve? 

:;.".  Give  live  principles  concerning  nerve  roots  and  their  branches. 

36.  Give  definition  for  nerve  center. 

:;7.  Give  name,  distribution,  function  ami  method  of  exit  of  the  1st  cranial 

nerve. 

38.  Same  of  2nd  cranial  nerve. 

.'!'.).  Same  of  3rd  cranial  nerve. 

Hi.  Same  of   1th  cranial  nerve. 

II.  Same  of  6th  cranial  nerve. 
•12.  Same  of  tith  cranial  nerve. 


ANATOMY    IN    A    NUTSHELL.  121 

43.  Same  of  7th  cranial  nerve. 

44.  Same  of  8th  cranial  nerve. 
4o.  Same  of  9th  cranial  nerve. 

46.  Same  of  10th  cranial  nerve. 

47.  Same  of  11th  cranial  nerve. 

48.  Same  of  12th  cranial  nerve. 

49.  What  is  the  lesser  circulation  of  the  blood? 

50.  What  is  the  greater  circulation  of  the  blood? 

51.  Who  demonstrated  the  circulation  of  the  blood? 

52.  Where  is  the  purest  blood  in  the  body  found? 

53.  What  kind  of  muscle  is  the  heart? 

54.  Capillaries  are  not  found  in  what  structures'.' 

55.  Which  are  the  larger,  arteries  or  veins? 

56.  What  do  you  understand  by  anastomosis? 

57.  Give  rule  for  arteries  and  veins  above  and  below  the  diaphragm. 

58.  Name  >ome  of  the  veins  that  do  not  have  valves. 

59.  Trace  the  fetal  circulation. 

60.  Name  the  things  obliterated  at  birth  in  the  fetal  circulation. 

61.  The  eight  cervical  nerves  leave  the  spinal  cord  above  the  spinous 
process  of  what  cervical  vertebra? 

62.  The  first  six  dorsal  nerves  leave  the  spinal  cord  between  the  spinous 
processes  of  what  vertebrae? 

63.  The  lower  six  dorsal  nerves  leave  the  spinal  cord  between  the  spinous 
processes  of  what  vertebrae? 

64.  The  five  lumbar  nerves  leave  the  spinal  cord    between  the  spinous 
processes  of  what  vertebrae? 

65.  The  five  sacral  nerves  leave  the  spinal  cord  between  the  spinous  pro- 
cesses of  what  vertebrae? 

66.  Bound  the  Axilla. 

Ii7.  Bound  the  Quadrilateral  Space. 

68.  What  pierces  the  Costo-coracoid  .Membrane? 

69.  Describe  the  Costo-coracoid  .Membrane. 

70.  What  structures  lie  in  the  Axilla'.' 

71.  What  structure-  pass  through  the  Quadrilateral  Space? 

72.  What  nerves  branch  from  each  cord  of  the  Brachial  Plexus? 

73.  What  and  how  many  muscles  are  supplied   by   the  musculocutane- 
ous? 

74.  What  and  how  many  muscles  are  supplied  by  the  median? 

75.  What  and  how  many  muscle-  are  supplied  by  the  circumflex? 

70.  What  and  how  many  muscles  are  supplied  by  the  musculo-spiral? 

77.  What  and  how  many  muscles  are  supplied  by  the  ulnar? 

78.  What  and  how  many  muscles  are  supplied  by  the  Subscapular  nerves? 
7'.i.  The  Rhomboid  nerves  come  from  which  one'.' 

80.  The  Posterior  Thoracic  comes  from  which  one-'.' 

81.  What  is  another  mime  tor  this  nerve? 

82.  The  Supra-scapular  come-  from  which  ones? 


1 22 


ANATOMY    IN    A     NUTSHELL. 


83.  <  rive  the  nerve  supply  of  integument  of  hand. 

84.  Give  the  nerve  supply  of  Lumbricales. 

85.  <  live  the  nerve  supply  of  [nterossei. 

86.  Group  the  musch  son  forearm;  give  nerve  supply. 

87.  Wha1  muscles  are  attached  to  the  External  Lateral  Ligament? 

ss.   \\  lint  muscl<  s  are  attached  to  the  Internal  Intermuscular  Septum? 

89.  Wha1  muscles  arc  attached  to  the  Externa]  Int<  rmuscular  Septum? 

90.  What  thr<  e  muscL  s  are  attached  to  the  Common  Aponeurosis? 

91.  What  passes  under  the  Anterior  Annular  Ligament? 

92.  What   passes  through  the  Anterior  Annular  Ligament? 

94.  W  Mat  musclt  s  are  attached  to  Ann  i  Lor  Annular  Ligament? 

95.  What    muscles  pass  through    the  six  openings   in    Posterior  Annular 
Ligament  ? 

96.  Give  the  three  divisions  of  Axillary  Artery. 

(.i7.  Give  the  relations  of  the  first  part  of  Axillary  Artery. 

98.  I  rive  the  relations  of  the  second  part  of  Axillary  Artery. 

99.  <  rive  the  relations  of  the  third  part  of  Axillary  Artery. 
LOO.  <  rive  the  branches  of  each  part  of  Axillary  artery. 

101.  Give  relations  of  Brachial  Artery. 

102.  Name  the  branches  of  Brachial  Artery. 
L03.   Give  the  relations  of  Radial  Artery. 

lo  I.   Name  the  branches  of  the  Radial  Artery. 

in.").  Give  relations  of  Ulnar  Artery. 

L06.  Give  the  branches  of  Ulnar  Artery. 

107.   Give  relations  of  Superficial  Palmar  Arch. 

ins.   What  pierces  the  Coraco-brachialis? 

109.  What  passes  between  the  two  heads  of  the  Pronator  radii  teres? 

110.  What  passes  between  the  two  heads  of  Flexor  carpi  ulnaris? 

111.  Whai  pierces  the  Internal  intermuscular  septum? 

112.  What   pierces  the  External  intermuscular  septum? 

1 13.  Desci Lbe  i he  ( lubital  fossa? 

1  1  I.    \\ "hat  passes  through  the  Cubital  fossa? 

1 15.   Name  I  be  bon<  sof  1  be  Carpus. 

I  16.  I  rive  articulation  of  each  hone. 

1  17.    Which  ones  have  muscles  attached  to  them? 

lis.   What  muscles  are  attached  to  the  Trapezium? 

1  19.   W  hat  muscles  are  attached  to  the  0s  magnum? 

120.  What  musclt  -  are  attached  to  the  Unciform? 

121.  What  muscles  arc  attached  to  the  Pisiform? 

122.  W  hat  musclt  -  are  attached  to  the  .Metacarpal  (each  hone)? 

1 23.  What  muscles  are  attached  to  the  Phalanges  of  the  thumb? 
P_' 1.  What  muscles  are  attached  to  the  Phalanges  of  the  fingers? 
125.   How  many  bones  in  the  hand? 

I  'jt\.  ( live  ligamenl  -  of  clavicle. 

127.  <  rive  Ligaments  of  scapula. 

128.  Give  ligaments  of  shoulder. 


ANATOMY    IN    A    NUTSHELL.  123 

129.  Give  ligaments  of  elbow. 

130.  Give  ligaments  of  forearm. 

131.  Give  ligaments  of  wrist. 

132.  What  kind  of  joint  is  Sterno-clavicular? 

133.  What  kind  of  joint  is  Acromio-clavicular? 

134.  What  kind  of  joint  is  the  shoulder? 

135.  What  kind  of  joint  is  the  elbow? 

136.  What  kind  of  joint  is  the  wrist? 

137.  From  what  do  cords  of  Brachial  plexus  take  their  names? 

138.  What  (-(inverts  the  Supra-scapular  notch  into  a  foramen? 

139.  What  vessels  pass  above  the  Transverse  Ligament? 

140.  What  structure  passes  below  the  Transverse  ligament? 

141.  What  structures  go  through  the  Musculo-spiral  groove? 

142.  What  holds  the  arm  in  position? 

143.  What  forms  the  Superficial  palmar  arch? 

144.  What  forms  the  deep  palmar  arch? 

145.  Give  the  Anastomosis  of  elbow-joint. 

146.  How  many  muscles  are  attached  to  the  clavicle? 

147.  How  many  muscles  are  attached  to  the  scapula? 

148.  How  many  muscles  are  attached  to  the  humerus? 

149.  How  many  muscles  are  attached  to  the  ulna? 

150.  How  many  muscles  are  attached  to  the  radius? 

151.  Name  the  muscles  lacking  origin  or  insertion  into  bone. 

152.  Describe  the  deep  fascia  of  arm. 

153.  Describe  the  deep  fascia  of  forearm. 

154.  Describe  the  Anterior  and  Posterior  Annular  ligaments. 

155.  Describe  synovial  membranes  of  wrist. 

156.  Name  principal  Flexor  and  Extensor  muscles  of  hand. 

157.  What  muscles  are  attached  to  the  greater  tuberosity? 

158.  What  muscle  is  attached  to  the  lesser  tuberosity? 

159.  The  pulse  is  felt  between  what  two  tendons? 

160.  How  does  the  radial  artery  get  into  the  palm  of  the  hand? 

161.  How  many  muscles  from  elbow  to  wrist? 

162.  What  nerve  lies  in  the  substance  of  the  Supinator  brevis? 

163.  Pronators  and  flexors  are  attached  to  which  condyle  of  humerus? 

164.  Extensors  and  supinators  to  which  condyle? 

165.  What   muscles  attached  to  external  or  anterior  bicipital  ridge? 

166.  To  the  posterior  or  internal  bicipital  ridge? 

167.  What  one  is  inserted  in  the  groove? 

168.  The  Musculo-spiral  nerve  divides  into  what  branches? 
1(19.    What  kind  of  nerve  is  the  radial? 

170.  Give   Anterior   carpal   arch. 

171.  Give  Posterior  carpal  arch. 

172.  How  does  the  posterior  interosseous  artery  gel   to  the  back  of  the 
forearm? 

173.  How  many  muscles  in  the  hand? 


124 


ANATOMY    IN    A    NUTSHELL. 


171.   What  relation  does  the  posterior  interosseous  artery  bear  to  the  deep 
layer  of  muscles  of  the  forearm? 
I  7").    1  describe  the  humerus. 
176.  With  what  does  it   articulate? 

PLATE  XLIII. 


POSTERIOR  LIMIT  OF  EXTERNAL  OBLIQUE. 


INSERTION  OF  EXTERNAL  OBLIQUE 


INTERNAL  OBLIQUE 


LUTEUS  KESIUS 

LATISSIMUS  DORS!. 

CREST  OF  ILIUM 


TENSOR  VAGINAE 
FEMORIS 


SAflTORIUS 
GLUTEUS  MINIMUS 


PECTINEAL  RIDGE 
"ECTINEUS 


RECTI  S  ABOOMINIS. 
PYRAMIOALIS 


•  ODIir.TnR  i  0NK5li'> 


REFLECTEO  TENDON  OF  RECTUS 


INTERNA,.  ILIAC  NOTCH 


ADOIlCTfUl  RRFVIS      —-"""^ 

OESCFuomr.  niMif.  if  "USES 
GRACILIS 


-fT        a  OBTURAT 

V'n      \  \    THYROID  ^^  T&-  ■    ■  .  \  ■■'3'  I    {*•     '■  .  '  1 — 


GLUTEUS  MAXIMUS. 


POSTERIOR 
SUPERIOR 
ILIAC  SPINE. 


POSTERIOR  INFERIOR  ILIAC  SPINE 
GREATER  SCIATIC  (ILIO-SCIATIC)  NOTCH 
CAPSULE. 

ISCHIUM 

SYNOVIAL  MEMBRANE 

GEMELLUS  SUPERIOR 
SPINE  OF  ISCHIUM 

-  LESSER  SCIATIC  NOTCH 
-GEMELLUS  INFERIOR 
OBTURATOR  NOTCH 
SEMIMEMBRANOSUS 


QtlADRATUS  FEMORIS 
'SEMITENDINOSUS  AND  BICEPS. 
ADDUCTOR  MAGNUS 


G8TURAT0R  EXTERMUS 

External  View  of  Left  Innominate  Hone. 

177.  How   many  and  what  muscles  attached  to  humerus,  ulna  and  radius? 

17s.  What  is  the  tongesl  muscle  inserted  on  the  humerus? 

179.  What  muscles  have  attachment  to  both  ulna  and  radius? 

L80.  With  how  many  bones  does  the  radius  articulate? 

181.  With  how  many  bones  doe-  the  ulna  articulate? 


ANATOMY    IN    A    NUTSHELL.  125 

182.  What  are  the  two  principal  veins  of  the  arm? 

183.  Which  one  passes  through  the  Axilla? 

184.  What  veins  form  each? 

185.  What  is  the  longest  nerve  in  the  arm? 

186.  How  many  openings  in  the  capsular  ligament  of  the  shoulder-joint? 

187.  Where  are  the  greater  and  lesser  sigmoid  cavities? 

188.  With  what  does  each  articulate? 

189.  Why  is  the  cephalic  vein  so  called? 

190.  Why  are  the  Lymphatics  so  called? 

191.  What  is  lymph? 

192.  What  else  are  lymphatics  called? 

193.  What  does  the  lymphatic  system  include? 

194.  Over  how  much  of  the  body  does  it  extend? 

195.  How  many  coats  have  the  lymphatics? 

196.  The  lymphatic  glands  of  the  arm  are  divided  into  how  many  sets? 

197.  The  lymphatic  vessels  are  how  divided? 

198.  Give  blood  supply  and  ossification  of  clavicle. 

199.  The  same  of  Scapula. 

200.  The  same  of  Humerus. 

201.  The  same  of  Radius. 

202.  The  same  of  Ulna. 

203.  The  same  of  Carpus. 

204.  The  same  of  Metacarpus. 

205.  The  same  of  Phalanges. 

206.  What  is  the  largest  nerve  of  Brachial  plexus? 

207.  What  separates  median  basilic  vein  from  brachial  artery? 

208.  Give  another  name  for  Supinator  longus. 

209.  Give  another  name  for  Extensor  brevis  pollicis. 

210.  Give  another  name  for  Extensor  longus  pollicis. 

211.  Give  another  name  for  First  dorsal  interosseous. 

212.  Give  Acromial  rete. 

213.  Deep  branch  of  ulna  passes  between  what  muscles? 

214.  Give  another  name  for  lesser  internal  cutaneous  nerve. 

215.  Give  another  name  for  the  long  thoracic  artery. 

216.  On  which  side  of  the  pisiform  bone  does  the  ulnar  artery  cross  the 
anterior  annular  ligament? 


LESSON   XXX II. 
Tin:  [lium.     (Plates  XLIII-XL1V.) 

The  ilium  which  forms  less  than  two-fifths  of  the  acetabulum  is  the  superior 
expanded  portion  of  the  innominate  bone.  This  portion  is  limited  superiorly 
by  the  arched  crest  of  the  ilium,  but  anteriorly  and  posteriorly  by  margins  which 
diverge  at  right  angles  from  each  other.  The  crest  is  concave  inward  in  front 
and  is  concave  outward  behind.     It  is  much  narrower  in  its  middle  than  near 


126  ANATOMY    IN    A    NUTSHELL. 

its  extremities,  and  there  is  often  a  marked  external  projection  in  its  anterior 
third.     On  the  cresl  are  external  and  internal  lips  and  an    intermediate  space. 

The  anterior  superior  spine  is  the  projection  at  the  anterior  extremity. 
below  which  is  a  concavity,  the  lesser  iliac  notch,  and  below  this  notch  is  the 
anterior  Inferior  spine.  The  posterior  superior  spine  is  the  projection  at  the 
posterior  extremity  of  the  crest,  and  is  separated  by  a  small  notch  from  the 
posterior  inferior  spine  below  which  i-  the  great  sciatic  notch. 

To  the  external  lip  from  before  backward  (Plate  XLIII)  are  attached  (1) 
Tensor  vaginae  femoris,  (2)  External  oblique  of  abdomen,  (3)  Latissimus  dorsi, 
P  Gluteus  maximus,  (5)  The  fascia  lata  throughout  the  entire  length  of  the 
lip. 

To  the  internal  lip  from  before  backward  (Plate  XLIV.)  are  attached  (1) 
Transversalis  abdominalis,  (2)  Quadratus  lumborum,  (3)  Erector  spina'.  (4) 
The  [liacus  muscle  and  iliac  fascia  to  that  part  of  this  lip  corresponding  to  the 
interna]  iliac  fossa. 

To  the  intermediate  space  i>  attached  the  Internal  oblique  of  the  abdomen. 
The  anterior  superior  spine  has  attached  1 1 )  T<  nsor  vaginae  femoris  externally. 
(2)   Sartorius  in  front.  (3)    Poupart's  ligament  internally. 

The  straight  head  of  the  Rectus  femoris  arises  from  the  anterior  inferior 
spine  of  the  Qii  m. 

Tin  external  surface  or  dorsum  ilii,  has  three  curved  lines  called  the  gluteal 
!iii'  -.  The  superior  or  POSTERIOR  gluteal  link  begins  two  inches  in  front  of 
the  post<  rior  superior  spine  and  curves  down  and  forward  to  the  hack  part  of 
the  ilio-sciatic  notch.  The  middle  gluteal  link  begins  in  front  about  an  inch 
and  a  half  b<  hind  the  ant<  rior  superior  spine,  and  arches  hack  and  down  to  the 
upper  part  of  die  notch.  The  inferior  gluteal  link,  not  so  well  marked. 
begins  jusl  above  the  anterior  inferior  spin<  .  and  passes  hack  to  the  fore  pari  of 
the  notch. 

The  Gluteus  maximus  is  attach*  d  bi  hind  th<  superior  gluteal  line  to  a  semi- 
lunararea  which  is  rough  above.  The  falciform  space  between  the  superior  and 
middle  curved  lines  and  the  iliac  cresl  is  occupied  by  the  Gluteus  medius.  The 
Gluteus  minimus  i<  between  the  middle  and  inferior  curved  lines.  The  re- 
flected  head  of  the  Rectus  femoris  is  attached  just  abov<  tin  cotyloid  cavity  to 
.•mi  oblong  mark. 

The  iliac  fossa  or  venter  ilii  is  the  ant(  ro-sup<  nor  pari  of  the  internal  sur- 
face and  is  larger  than  the  postero-inferior  part.  It  ,<dv<  s  attachment  to  the 
I  liacus  muscle  exc<  pi  at  its  ant<  ro-inf<  rior  portion.  The  vi  nter  is  smooth  and 
concave.     The  ilio-pt  ctineal  line  s<  parat<  s  this  pai  t  from  the  true  pelvis. 

To  the  inner  side  of  the  anterior  inf<  rior  -pine  is  a  shallow  groove,  the  great 
iliac  notch,  which  lodges  the  Qio-psoas  muscle  as  it  passes  under  Poupart's  lig- 
am<  nt  ;  the  inni  r  boundary  i  f  the  groove  is  the  ili<  -pectineal  eminence,  making 
the  junction  of  the  pubis  ami  ilium.  The  p<  stero-inferior  part  is  again  divided, 
mi  below  upward  (1)  a  smooth  curved  surface  in  the  true  pelvis, 
giving  attachment  in  part  to  a  portion  of  the  <  Obturator  interims,  separated  from 
the  iliac  fossa  by  the  iliac  portion  of  the  i!io-p<  ctineal  line:  (2)  the  auricular 
surface,  for  articulation  with  the  sacrum;  (3)  depr(  ssion  for  the  posterior  -aero- 


ANATOMY    IN    A    NUTSHELL. 


127 


iliac  ligament;  (4)  a  rough  surface  giving  origin  to  the  Erector  and  Multifidus 
spinae  muscles. 

Blood  Supply:— The  ilium  receives  on  its  anterior  surface  twigs  from  the 
ilio-lumbar,  deep  circumflex  iliac,  and  obturator  arteries.  On  the  dorsum  arter- 
ies enter  it  from  the  gluteal  and  sciatic  funks. 

PLATE  XLIV. 


QUAORATUS  LUMBORUM. 


s6  'l^^-fr^W^^ltffc^X-?* 


TRANSVERSALISAND 
•THE  ILIAC  FASCIA. 


ERECTOR  SPINAE.- 


I       L       I,      U       «. 


MULTIFIDUS  SPINAE. 


INTERNAL  ILIAC  FOSS/L"^      /'>/.4>1^\ 

,     I    A   c  '(/-.;.•  - :   >Jfc       • 


E?W 


*Tfc 


POST.  INF.  SPINE  OF  ILIUM. 


;•'.'  I   v'  AURICULAR  SURFACE; 


OBTURATOR  INTERNUS. 


i     ,.  i 


GROOVE  FOR  PUDIC  VESSELS  AND  NERVE 


GREAT  SACRO-SCIATIC  LIGAMENT 


ANT  SUP  SPINE  OF  ILIUM. 


ANT  INF   SPINE  OF  ILIUM. 


PSOAS  PARVUS 
ILIO-PECTINEAL  EMINENCE 


GROOVE  FOR  OBTURATOR 
NERVE   AND  VESSELS. 


'      <f$r           \       JM   P    U'-B    E   S.  •    . 
'     /j  ~      JJk    '       '' '^■'^i^4^WL SYMPHYSIAL  SURC»CE 

08TIIRAT0R  '    •  /  [  '  .     "'.      '  /?$ 

I        FORAMEN.      /;"/'.'( 


/      l 


««   ;R" 


TUBEROSITY  OF  ISCHIUM. 

TRANSVERSUS  PERINEI 

JUNCTION  OF  PUBES  AND  ISCHIUM 


>■  •'  ^ 

'  /H  ^"LEVATOR  ANI 

SUBPUBIC  LIGAMENT 
COMPRESSOR  URETHRAL 
CRUS  PENIS' ANO  ERECTOR  PENIS. 


[nternal  View  of  Left  [nnominate   Bone. 

The  ischium  is  supplied  by  the  obturator,  internal  and  ext<  rnal  circumflex. 
The  pubis  receives  twigs  from  the  obturator,  internal  and  external  circum- 
flex, deep  epigastric,  and  pubic  branch  of  the  common  femoral  artery. 
These  three  bones  form  the  is  innominatum. 


128  ANATOMY    IN    A    NUTSHELL 

Ossification  from  eight  centers. 

There  is  one  primary  center  for  the  ilium  which  appears  at  the  eighth  or 
ninth  week.  One  for  the  ischium  at  about  the  third  month,  and  one  for  the  os 
pubis  between  the  fourth  and  fifth  month.  These  three  primary  centers  unite 
through  a  Y-shaped  piece  at  about  the  age  of  puberty.  There  are  five  secondary 
centers-  one  for  the  crest  of  the  ilium,  one  for  the  anterior  inferior  spin- 
01  -  proi  ess,  one  for  the  tuberosity  of  the  ischium,  one  for  the  symphysis 
pubis,  and  one  or  more  for  the  bottom  of  the  acetabulum.  Epiphyses  appear 
about  the  age  of  puberty  and  unite  with  the  rest  of  the  bone  between  the 
twentieth  and  twenty-fifth  years. 

Articulates  with  its  fellow  of  the  opposite  side,  the  sacrum  and  femur. 

Attachment  ok  muscles  to  the  ilium,  sixteen.  To  the  outer  lip  of  crest, 
the  (1)  Tensor  vagina1  femoris,  (2)  Obliquus  externus  abdominis,  and  (3)  Lat- 
issimus  dorsi;  to  the  internal  lip.  the  (4)  Iliacus,  (5)  Transversalis,  (6)  Quad- 
rants lumborum,  and  (7)  Erector  spina?;  to  the  interspace  between  the  lips,  the 
(8)  Obliquus  internus.  To  the  outer  surface  of  the  ilium,  the  (9)  Gluteus  max- 
inii!-.  (10)  Gluteus  medius,  (11)  Gluteus  minimus,  reflected  tendon  of  the  (12) 
Meet ns;  to  the  upper  part  of  the  great  sacro-sciatic  notch,  a  portion  of  the  (13) 
Pyriformis;  to  the  internal  surface,  the  Iliacus,  to  that  portion  of  the  internal 
surface  below  the  linea  ilio-pectinea,  the  (14)  Obturator  internus  and  the  (15) 
Multifidus  spina'  to  the  internal  surface  of  the  posterior  superior  spine;  to  the 
.interior  border,  (16)  the  Sartorius  and  straight  tendon  of  the  Rectus. 

To  the  ischium,  fourteen: — To  the  outer  surface  of  the  ramus,  the  (1)  Ob- 
turator externus  and  (2)  Adductor  magnus;  to  the  internal  surface,  the  (3)  Ob- 
turator internus  and  (4)  Erector  penis.  To  the  spine,  the  (5)  Gemellus  superior, 
(6)  Levator  ani,  ami  (7)  Coccygeus.  To  the  tuberosity,  the  (8)  Biceps,  (9)  Semi- 
tendinosug,  (KM  Semimembranosus,  (11)  Quadratus  femoris,  (12)  Adductor 
magnus,  (13)  Gemellus  inferior,  (14)  Transversus  perinsei,  Erector  penis. 

To  the  os  pubis,  sixteen:  (l)Obliquus  externus,  (2)  Obliquus  internus,  (3) 
Transversalis.  (4)  Rectus,  (5)  Pvramidalis,  (6)  Psoas  parvus,  (7)  Peetincus,  (8) 
Adductor  magnus.  (9)  Adductor  longus,  (10)  Adductor  brevis,  (11)  Gracilis, 
(12)  Obturator  externus,  (13)  Obturator  internus,  (14)  Levator  ani,  (15)  Com- 
pressor met  In  a',  and  occasionally  a  few  filters  of  the  (16)  Accelerator  urinae. 


LESSON  XXXI II. 

Tin:  Os   Pubis. 

The  os  pubis  which  consists  of  a  body  and  two  rami  forms  the  anterior  wall 
of  the  pelvis,  and  bounds  the  obturator  foramen  above  and  partly  in  front.  The 
SYMPHYSIS  PUBIS  is  the  junction  of  this  bono  with  its  fellow.  It  is  the  inner  ex- 
tremity of  the  bone  fat  Lng  inward  b<  ing  of  an  oblong  surface  marked  by  trans- 
\  erse  ridg<  s.  The  des<  ending  r  \.\us  pass<  s  down  and  out  from  the  symphysis. 
It  is  thin  and  Hat  ami  joins  the  ramus  of  the  ischium  at  a  point  little  more  than 
half  way  from  the  body  of  the  pelvis  to  the  tuberosity  of  the  ischium.  The 
superior  or  ascending  ramus  is  the  upper  part  of  the  bone.     This  ramus  ends 


ANATOMY    IX    A    NUTSHELL.  129 

externally  at  the  cotyloid  cavity  and  forms  more  than  one-fifth  of  it.  The  su- 
perior border  of  this  ramus  forms  the  pubic  portion  of  the  ilio-pectineal  line, 
running  from  the  spine  of  the  pubis  to  the  internal  aspect  of  the  ilio-pectineal 
eminence. 

The  part  between  the  two  rami  is  the  body  of  the  os  pubis.  Its  anterior 
surface  is  rough  and  its  pelvic  surface  is  smooth.  The  Pectineus  muscle  has  its 
origin  from  the  ilio-pectineal  line  and  the  triangular  surface  in  front  of  it.  The 
obturator  crest  extends  from  the  pubic  spine  to  the  acetabulum  below  the 
ilio-pectineal  line.  The  obturator  groove  is  on  the  inferior  surface  of  the 
ramus  behind  the  outer  part  of  the  crest.  It  is  directed  from  behind  forward 
and  inward. 

The  pubic  crest  gives  origin  to  part  of  the  (1)  Conjoined  tendon,  (2)  the 
Pyramidalis  and  (3)  Rectus  abdominis.  To  the  pubic  spine  are  inserted  (1) 
Poupart's  ligament  and  the  (2)  outer  pillar  of  the  external  abdominal  ring. 
From  the  front  of  the  pubis,  in  the  angle  between  the  crest  and  the  symphy- 
sis, arises  the  (1)  Adductor  longus  muscle,  and  below  this  the  (2)  Adductor 
brevis  and  part  of  the  (3)  Adductor  magnus.  Internal  to  these  the  (1) 
Gracilis  is  attached,  and  external  the  (2)  Obturator  externus.  Posteriorly 
the  pubis  gives  attachment  to  the  (1)  Obturator  internus;  above  this  is  some- 
times a  flat  line  passing  from  the  upper  margin  of  the  obturator  foramen  to 
the  lower  end  of  the  symphysis;  the  (1)  Levator  ani  muscle  is  attached  to  it.  and 
(2)  the  Obturator  and  recto-vesical  fasciae. 

The  Ischium. 

The  ischium  forms  the  lower  and  back  part  of  the  innominate  bone.  It 
forms  a  little  more  than  two-fifths  of  the  cotyloid  cavity  and  bounds  the  obtura- 
tor foramen  below. 

This  bone  has  a  body,  a  tuberosity,  and  a  ramus.  The  body  has  three  sur- 
faces and  three  borders.  The  surfaces  are  external,  internal  and  posterior. 
The  borders  are  also  external,  internal  and  posterior. 

The  external  surface  helps  form  the  acetabulum,  and  this  part  is  smooth 
and  concave.  Immediately  below  the  acetabulum  is  a  horizontal  groove  for  the 
Ten i Ion  of  the  Obturator  externus. 

The  internal  surface  forms  part  of  the  wall  of  the  true  pelvis.  In  shape  it 
is  roughly  quadrilateral,  also  smooth  and  concave  to  a  small  degree.  A  ridge 
showing  its  junction  with  the  ilium  is  its  upper  limit.  Its  anterior  limit  is  its 
junction  with  the  os  pubis  and  the  obturator  foramen.  Its  posterior  limit  is 
the  anterior  margin  of  the  great  sciatic  notch.  Its  lower  limit  is  the  tuberosity. 
A  part  of  the  Oubtrator  internus  muscle  is  attached  to  this  surface. 

Posterior  surface  is  limited  in  front  by  the  margin  of  the  cotyloid  cavity. 
It  is  limited  behind  by  the  posterior  margin  of  the  bone.  It  is  limited  above  by 
its  connection  with  the  ilium,  and  it  is  limited  below  by  the  tuberischii.  This 
surface  supports  the  two  Gemelli,  the  Pyriformis  and  the  Obturator  internus. 
Below  it  presents  a  pari  of  the  groove  tor  the  Obturator  externus. 

The  external  border  is  synonymous  with  that  part  of  the  rim  of  the  Aceta- 
bulum which  belongs  to  the  ischium. 


130 


ANATOMY   IN  A   NUTSHELL. 


The  internal  border  is  synoynmous  with  the  outer  boundary  of  the  obtura- 
tor foramen. 

The  posterior  border  has  the  spine  of  the  ischium  a  little  below  its  middle. 
This  spine  which  extends  backward  and  inward  marks  the  lower  limit  of  the 
greal  sciatic  notch.  It  gives  attachment  to  the  Levator  ani  and  (occygeus 
muscles,  externally  to  the  Gemellus  superior.  Between  this  spine  and  the  tuber- 
osity is  the  lesser  sciatic  notch.  The  tuberosity  has  three  surfaces — ex- 
ternal, internal,  and  postero-inferior. 

The  external  SURFACE  of  the  tuberosity  is  lost  below  in  the  ramus  and 
above  with  the  groove  for  the  tendons  of  the  Obturator  externus.  It  is  limited 
in  front  by  posterior  margin  of  the  thyroid  foramen,  and  externally  by  the  pos- 

PLATE  XLV. 

ARTICULAR 

PROCESS. 


SACRAL 
FORAMEN 


ERECTOR 
SPINA!. 


MULTIF1DUS 
SPINA!. 

GLUTEU 

MAXI 


HIATUS 

SACRALIS, 

LEADING  INTO 

SACRAL CANAL 


SACRAL  CORNU 


GLUTEUS  MAXIMUS 


SPHINCTER   ANI 


COCCYX. 


Posterior  View  of  Sacrum  and  Coccyx. 

tero-inferior  surface.     The  muscks  attached  to  this  surface  are  the  Quadratus 
femoris  on  the  posterior  aspect,  the  Obturator  externus  on  the  antero-inferior 

aspect,  and  the  Adductor  magnUS  below  these  two. 

The  [NTERNAL  SURFACE  of  the  tuberosity  extends  to  the  thyroid  foramen 
in  front.  Behind  and  below  it  ends  in  a  prolongation  tor  the  attachment  of 
the  greal  sciatic  ligament. 

The  i'o-i  bro-inferior surface  of  t he  tuberosity  has  the  Semimembranosus 
attached  to  its  upper  and  outer  portion,  while  the  Biceps  and  Semitendinosus 
are  attached  to  its  lower  and  inner  portion. 

The  ramus  of  the  ischium  is  not  as  long  as  the  ramus  of  the  OS  pubis  which 


ANATOMY    IN    A    NUTSHELL.  131 

it  joins  at  a  little  less  than  half  the  distance  between  the  body  of  the  os  pubis 
and  the  tuberosity  of  the  ischium.  The  Obturator  externus,  the  Adductor 
magnus  and  the  Gracilis  are  attached  to  its  outer  surface.  The  Crus  penis  and 
Transversus  perinei  are  attached  to  its  inner  border. 

The  cotyloid  cavity,  or  acetabulum,  is  cup  shaped.  It  looks  outward,  for- 
ward and  downward.  The  Ilium  forms  a  little  less  than  two-fifths  of  the  aceta- 
bulum. The  os  pubis  forms  a  little  more  than  one-fifth  of  the  acetabulum. 
The  Ischium  forms  a  little  more  than  two-fifths  of  the  acetabulum.  The  rim 
of  this  cavity  is  prominent,  but  it  is  slightly  lower  in  front  and  behind  and  has 
a  large  notch  below  called  the  cotyloid  notch.  The  depression  in  the  center  is 
called  the  cotyloid  fossa,  around  which  is  the  articular  portion  of  the  cotyloid 
cavity. 

The  thyroid  or  obturator  foramen — sometimes  called  foramen  ovale  is  be- 
low and  internal  to  the  acetabulum.  This  foramen  is  closed  by  a  fibrous  mem- 
brane, leaving  a  space  for  the  obturator  groove  in  its  upper  margin.  In  the 
male  this  foramen  is  nearly  oval,  while  in  the  female  it  is  more  triangular. 

LESSON  XXXIV. 

The  Pelvis  as  a  Whole. 

The  word  pelvis  means  basin.  It  is  composed  of  four  bones,  the  sacrum, 
coccyx,  and  the  two  innominate.  If  we  pass  a  plane  through  the  sacral  pro- 
montory, ilio-pectineal  line  and  the  upper  border  of  the  symphysis,  we  divide 
the  pelvis  into  an  upper  or  false  pelvis  and  a  lower  or  true  pelvis.  The  upper 
pelvis  really  belongs  to  the  abdomen.  The  sacrum  looks  downward  and  for- 
ward. Its  anterior  surface  is  broader  than  its  posterior  surface.  It  is  held  in 
place  by  ligaments  and  the  projections  into  the  iliac  articular  surface.  The 
plane  separating  the  true  and  false  pelvis  marks  an  angle  of  60  degrees  with  the 
horizontal.  The  plane  of  this  outlet  makes  an  angle  of  16  degrees  with  the  hor- 
izontal. 

The  base  of  the  sacrum  is  about  three  and  one-half  inches  above  the  upper 
margin  of  the  symphysis.  The  tip  of  the  coccyx  is  one-half  inch  above  the  apex 
of  the  subpubic  arch. 

The    ANTEROPOSTERIOR    DIAMETER,    CALLED    THE    CONJUGATE    DIAMETER,    LS 

measured  from  the  sacro-vertebral  angle  to  the  symphysis. 

The  transverse  diameter  represents  the  greatest  width  of  the  pelvic  cav- 
ity. 

The  oblique  diamkteh  is  measured  from  the  sacro-iliac  joint  of  one  side 
to  the  ilio-pectineal  eminence  of  the  other. 

The  average  measurements  of  the  diameters  of  the  pelvis  in  the 
three  planes  are  as  follows: 

antero-posterior.  oblique.  i  i;  \\s\  i:nsK. 

Inlet 4  1-4  inches 5     inches 5   1-1   inches 

Cavity 4  3-4  inches •">  1-4  inches 5  :^-4  inches 

Outlet  .  ,         .3  3-4  inches    .  ..4   1-2   inches 4    1-4  inches 


132  ANATOMY    IN    A    NUTSHELL. 

THE  FEMALE  PELVIS  DIFFERS  FROM  THE  MALE  PELVIS  IN  THE  FOLLOWING 
RESPE'   I  s: 

I  |  The  bones  are  more  slender.  (2)  ilia  more  vertical,  (3)  iliac  fossa  is 
shallower,  (4)  false  pelvis  is  relatively  narrower,  (5)  the  true  pelvis  is  shallower, 
also  (6)  true  pelvis  is  wider,  (7)  inlet  is  more  oval,  (8)  symphysis  is  shallower, 
i'.ii  tuberosities  of  ischia  are  everted.  (10)  pubic  arch  is  wider  and  more  round- 
ed, ill)  margins  of  ischio-pubic  rami  are  less  everted,  (12)  obturator  foramen 
is  triangular,  while  in  the  male  it  is  oval,  (13)  sacrum  is  wider  and  less  curved, 
and  (14)   the  capacity  of  the  true  pelvis  is  greater. 

The  Sacrum. 

The  sacrum  is  formed  by  the  coalescence  of  five  segments.  It  forms  the 
upper  and  back  part  of  the  pelvis,  being  placed  between  the  two  innominate 
bones.  It  is  a  wedge  shaped  bone  with  its  apex  below,  and  its  anterior  surface 
wider  than  its  posterior  surface. 

The  anterior  border  of  the  upper  portion  or  base  is  called  the  promontory. 
It  has  four  surfaces,  a  base,  an  apex,  and  a  central  canal. 

The  anterior  surface  has  four  ridges  marking  the  junction  of  the  five  seg- 
ments. This  surface  is  concave,  both  vertically  and  transversely  (less  so.) 
The  five  segments  or  vertebras  decrease  from  above  downward.  At  the  ends  of 
the  transverse  ridges  are  foramina  for  the  transmission  of  the  sacral  nerves. 
These  f<  »ramina  are  directed  forward  and  outward.  At  the  sides  of  the  foramina 
are  the  lateral  masses  formed  by  the  transverse  processes  of  the  vertebrae  of 
the  sacrum. 

The  posterior  surface  is  not  as  wide  as  the  anterior  one  and  is  convex.  It 
has  rudimentary  spinous  processes  in  its  median  line.  There  are  usually 
three  orfour  of  these,  the  fifth  one  being  undeveloped.  External  to  the  processes 
are  the  i.amive.  the  first  three  are  well  marked;  the  fourth  is  not  well  developed 
and  the  fifth  is  rarely  so.  The  fifth  ones  are  prolonged  downward  forming  the 
sacral  cornua.  External  to  the  laminae  are  the  articular  processes,  the  first 
pair  are  Large,  the  second  and  third  small,  and  fourth  and  fifth  are  most  always 
fused.  Externa]  to  the  articular  processes  are  the  foramina  for  the  posterior 
divisions  of  the  sacral  nerves.  External  to  the  foramina  are  the  transverse 
processes. 

The  sacral  groove  is  wide  and  shallow  lodging  the  Erector  spinas.  It  lies 
between  the  spinous  and  transverse  processes. 

The  lateral  surface  is  narrow  behind  but  broad  above.  The  upper  half  of 
this  surface  is  called  the  auricular  surface.  It  articulates  with  the  ilium  and  is 
covered  with  fibro-cartilage  in  the  recent  state.  Behind  this  articular  surface 
are  deep  impressions  for  the  attachment  of  the  posterior  sacro-iliac  ligaments. 
The  lower  half  of  this  surface  is  called  the  tuberosity,  and  the  borders  of  this 
half  of  the  surface  give  attachment  to  the  sacro-sciatic  ligaments  and  part  of 
the  ( rluteus  maxiinus. 

The  base  is  the  pari  which  articulates  with  the  last  lumbar  vertebra.  It  is 
broad  and  look-  upward  and  forward.  Its  anterior  part  is  for  the  interarticular 
fibro-cartilage  and  is  oval.      Its  posterior  part  has  the  sacral  canal  which  is 


ANATOMY    IN    A    NUTSHELL. 


133 


formed  by  the  laminae  and  spinous  process.  The  superior  articular  processes  are 
oval  and  concave.  They  are  situated  on  each  side  of  the  sacral  canal  and  are 
directed  backward  and  inward.  The  intervertebral  notches  are  in  front  of  these 
processes. 

The  al.e  are  flat  triangular  areas  on  each  side  of  the  articular  processes, 
and  are  continuous  with  the  iliac  fossa.  The  Iliacus  muscle  has  a  \'v\v  fibers  of 
origin  from  the  ala. 

The  apex  articulates  with  the  coccyx  and  is  directed  downward  and  for- 
ward. 

PLATE  XLVI. 


PROMONTORY. 

ARTIC.WITH 
LAST   LUMBAR. 


COCCYGE 


LEVATOR  ANl 


Anterior  View  of  Sacrum  and  Coccyx. 

The  spinal  canal  is  larger  and  triangular  above,  but*below  it  is  ilattened 
from  before  backward.  The  lower  part  of  its  posterior  wall  is  incomplete.  This 
is  caused  by  the  non-development  of  the  laminse  and  spinous  processes. 

Ossification  : — Thirty-five  centers. 

Articulation: — With  four  bones;  the  lasl  Lumbar  vertebra,  coccyx,  and 
the  two  ossa  innominata. 

Attachment  of  Muscles: — Eight  pairs;  in  front,  the  Pyriformis  and 
Coccygeus,  and  a  portion  of  the  Iliacus  to  the  base  of  the  bone:  behind,  the 
Gluteus  maximus,  Latissinnis  dorsi.  Multifidus  spinse,  and  Erector  spinae,  and 
sometimes  the  Extensor  coccveeus. 


i;^4  anatomy  in  a  nutshell. 

The  Coccyx. 
The  coccyx  is  formed  by  four  and  sometimes  five  segments.     It  has  no 

SPINAL  CANAL,    [NTERVERTEBRAL  FORAMINA.   SPINOUS  PROCESSES,   LAMIN.E,    PED- 

[CLES.  The  firsl  segmenl  may  be  separate  bu1  the  rest  are  united  and  run  to  a 
point.  This  bone  has  an  anterior  and  posterior  surface,  two  borders,  a  base, 
and  an  apex. 

The  anterior  surface  has  three  transverse  grooves  marking  the  union  of  the 
ments.      This  surface  is  concave. 

The  posterior  surface  is  convex  and  has  grooves  similar  to  those  on  the  an- 
terior.  The  upper cornua  are  large  and  articulate  with  thecornua  of  the  sacrum 
making  the  fifth  posterior  sacral  foramina. 

The  lateral  borders  are  thin  and  present  small  eminences — the  rudimentary 
transverse  processes.  The  upper  pair  of  the  processes  may  articulate  with  the 
inferior  lateral  angles  of  the  sacrum,  thus  forming  the  fifth  anterior  sacral  for- 
amina.    The  other  processes  are  small  and  may  be  absent. 

Blood  Supply: — Sacra  media. 

(  )ssification: — Four  centers. 

Articulation: — With  the  sacrum. 

Attachment  of  Muscles: — Four  pairs  and  one  single  muscle;  on  either 
side,  the  Coccygeus;  behind,  the  Gluteus  maximus  and  Extensor  coccygeus, 
when  preseni  ;  at  the  apex,  the  Sphincter  ani;  and  in  front,  the  Levator  ani. 


LESSON  XXXV. 

Psoas  magnus. — Description. — (Plate  LXXIII.)  In  the  posterior  part  of 
the  substance  of  this  muscle,  the  lumbar  plexus  is  situated.  This  muscle,  which 
is  placed  on  each  side  of  the  spine  in  the  lumbar  region  and  the  margin  of  the 
pelvis,  is  a  Long  and  fusiform  one.  It  is  attached  by  five  slips  to  the  interverte- 
bral substance  and  the  adjacent  parts  of  the  vertebra  above  and  below.  Be- 
tween  these  slips  are  tendinous  arches  which  with  the  concave  part  of  the  body 
of  each  lumbar  vertebra  make  a  passage  for  the  lumbar  vessels  and  filaments  of 
the  sympathetic  nerve.  As  the  muscle  passes  down  it  decreases  in  size  and 
passing  under  Poupart's  ligament,  it  terminates  in  a  tendon  after  having  re- 
reived  nearly  all  the  fibers  of  the  Iliacus. 

Origin: — (Plate  LXXIII.)  (1)  Front  of  bases  of  lumbar  vertebrae  by 
live  fleshy  slips;  (2)  -ides  of  bodies  and  intervertebral  substances  of  last  dorsal 
and  all  the  Lumbar  vertebrae. 

Insertion:     (Plates  XLVIII-XLIX.)     Lesser  trochanter  of  the  femur. 

A(  pion:     1'lexes  thigh  on  pelvis;  maintains  erect  posture. 

N  i  RVE  Si  I'i'iA  :     Anterior  branches  of  second  and  third  lumbar  nerves. 

Blood  Si  pply: — Dio-lumbar  from  posterior  branch  of  internal  iliac,  and 
lumbar  from  abdominal  aorta. 

Psoas  parvus.  Description.— (Plate  LXXIII.)  This  muscle  may  be 
absenl  or  double.  It  is  situated  in  front  of  the  Psoas  and  ends  in  a  long  flat 
tendon.  It  is  well  developed  in  those  animals  which  are  swift  runners,  in  that 
it  flexes  the  pelvis  and  arches  the  Lumbar  spine. 


ANATOMY    IN    A    NUTSHELL.  135 

Origin: — (Plate  LXXIII.)  Sides  of  bodies  of  last  dorsal  and  first  Lumbar 
vertebra?  and  substance  between. 

Insertion: — (Plate  XLIV.)  Ilio-pectineal  eminence  and  by  its  outer 
border  into  the  iliac  fascia. 

Action: — Same  as  Psoas  magnus,  also  makes  tense  the  iliac  fascia. 

Nerve  Supply: — Anterior  branch  of  first  lumbar. 

Blood  Supply: — Lumbar  from  abdominal  aorta. 

Iliacus. — Description. — (Plate  LXXIII.)  The  Iliacus  and  the  Psoas 
magnus  are  sometimes  regarded  as  one  muscle,  the  Ilio-psoas,  since  they  have 
one  insertion.  The  Iliacus  which  is  flat  and  triangular  fills  the  whole  of  the 
iliac  fossa. 

Origin. — (Plates  XLIV-XLVL) — (1)  Upper  two-thirds  of  iliac  fossa  and 
inner  margin  of  crest  of  ilium;  (2)  in  front,  anterior  superior  and  inferior  spin- 
ous process  of  ilium  and  notch  between:  (.'->)  behind,  ilio-lumbar  ligament  and 
base  of  sacrum;  (4)  fibers  from  capsule  of  hip-joint. 

Insertion. — (Plate  XLVIII.) — Outer  side  of  tendon  of  Psoas  muscle  and 
into  oblique  line  extending  from  lesser  trochanter  to  linea  aspera. 

Action. — Flexes  thigh  on  pelvis  and  rotates  femur  outward;  also  aids  in 
maintaining  erect  posture. 

Nerve  Supply. — Anterior  branches  of  second  and  third  lumbar  through 
the  anterior  crural. 

Blood  Supply. — Ilio-lumbar. 

Tensor  vagina3  femoris. — Description. — (Plate  LXIV.) — This  muscle  lies 
along  the  outer  side  of  the  thigh  and  extends  from  the  crest  of  the  ilium  to  about 
one-fourth  the  distance  to  the  knee. 

Origin. — (Plate  XLIII.) — Anterior  portion  of  outer  lip  of  crest  of  ilium 
and  outer  surface  of  anterior  superior  spinous  process  between  Gluteus  medius 
and  Sartorius  muscle,  and  from  fascia  covering  the  Gluteus  medius. 

Insertion. — (Plate  LXIV.) — Between  the  two  layers  of  the  fascia  lata. 
The  fascia  is  continued  downward  to  external  tuberosity  of  the  tibia  as  a  thick- 
ened band,  the  ilio-tibial  band. 

Action. — Tenses  fascia  lata. 

Nerve  Supply. — Fourth  and  fifth  lumbar  and  first  sacral  through  the 
superior  gluteal. 

Blood  Supply. — Superior  gluteal  and  external  circumflex. 

Sartorius. — Description. — (Plate  LXXIY.) — This  muscle,  which  extends 
from  the  ilium  to  the  tibia,  is  flat,  narrow,  ribbon-like,  and  i<  the  longest  one  in 
the  body.  In  the  upper  part  of  its  course  it  forms  the  outer  boundary  of  Scar- 
pa's triangle.  It  passes  downward,  then  obliquely  inward,  then  downward  to 
the  insertion. 

Scarpa's  triangle  (Plates  LXIV-LXXIV.) — Is  bounded  above  by  Pouparl  'a 
ligament.  On  the  outer  side  by  the  Sartorius  and  on  its  inner  side  by  the  Ad- 
ductor longus.  The  femoral  vessels  and  the  anterior  crural  nerve  pass  through 
it-  center  from  above  down.  Their  position  from  within  outward  is  femoral 
vein,  artery,  and  anterior  crural  nerve  (V.  A.  N.).  The  floor  of  this  triangle  from 
without  inward  is  formed  by  the  Iliacus,  Psoas,  IVctineus,  (Adductor  brevis?) 


136 


ANATOMY    IN    A    NUTSHELL. 


and  Adductor  longus.  In  the  middle  third  of  the  thigh  the  femoral  artery  lies 
first  along  the  inner  border  and  then  behind  the  Sartorius. 

Origin. — (Plate  XLIII). — Anterior  superior  spinous  process  of  ilium  and 
upper  half  of  notch  below. 

Insertion.-  (Plate  LI.) — The  muscle  passes  behind  the  inner  condyle  of 
the  femur  and  terminates  in  a  tendon  which,  curving  obliquely  forward,  ex- 
pands  into  a  broad  aponeurosis  and  is  inserted  into  the  upper  part  of  the  inner 
surface  of  the  shaft  of  the  tibia,  nearly  as  far  forward  as  the  crest.     An  offset  is 

PLATE  XLVII. 


Anterior  and  Superior  View  of  the  Pelvis. 
derived  from  the  upper  margin  of  this  aponeurosis  which  blends  with  the  fi- 
brous  capsule  of  the  knee-joint,  and  another,  given  off  from  its  lower  border, 
blend.-  with  the  fascia  OH  t  lie  inner  side  of  the  leg. 

A(  i  u )\.      Flexes  leu  on  thigh  and  continuing  to  act  flexes  the  thigh  on  the 
pelvis;  also  rotates  the  thigh  outward. 

\i.i;\  i.  Si  pply.     Branch  of  anterior  crural. 

Blood  Supply.-    Femora]  artery. 

Rectus    lemons.      Description.— (Plates    LXIV-LXV111-LXXIV.)— The 
Rectus  fenioris  together  with  the  Vastus  externus,  Vastus  interims,  and  the 


ANATOMY    IN    A    NUTSHELL.  137 

Crureus,  form  one  muscle — the  Quadriceps  extensor,  which  is  the  great  extensor 
of  the  leg.  This  might  be  called  one  muscle  with  four  heads  and  one  insertion. 
The  Rectus  is  situated  in  the  middle  and  anterior  part  of  the  group  and  has  two 
heads.  These  heads  join  at  an  acute  angle.  Its  superficial  fibers  are  bipenni- 
form.  and  its  deep  ones  run  straight  down  to  the  deep  aponeurosis.  The  broad 
and  thick  aponeurosis  which  occupies  the  lower  two-thirds  of  the  posterior  sur- 
face of  the  muscle  gradually  ends  in  a  flattened  tendon. 


LESSON  XXXVI. 

Origin. — (Plate  XLIII.) — The  anterior  or  straight  tendon,  from  the  an- 
terior inferior  spinous  process  of  ilium;  the  posterior,  or  reflected  tendon,  from 
a  groove  above  the  brim  of  the  acetabulum. 

Insertion. — (Plate  LXXIV.) — Into  the  patella  in  common  with  the  Vasti 
and  Crureus. 

Action. — Assists  Psoas  muscle  to  bend  pelvis  and  trunk  forward  and  sup- 
port them  upon  the  femur. 

Nerve  Supply. — Anterior  crural. 

Blood  Supply. — Femoral  artery. 

Vastus  externus. — Description. — (Plates  LXIV-LXVIII-LXXIV.) — This 
muscle  is  the  largest  part  of  the  Quadriceps  extensor.  The  strong  aponeurosis 
on  the  under  surface  at  the  lower  part  of  this  muscle  receives  the  fillers  which 
form  a  large  fleshy  mass.  The  tendon  of  this  muscle  gives  an  expansion  to  the 
capsule  of  the  knee-joint. 

Origin. — (Plate  XLVIII.) — By  a  broad  aponeurosis  attached  to  ihe  upper 
half  of  anterior  intertrochanteric  line,  to  the  anterior  and  inferior  borders  of  the 
root  of  the  great  trochanter,  to  the  outer  lip  of  the  gluteal  ridge,  and  to  the 
upper  half  of  the  outer  lip  of  the  linea  aspera.  This  aponeurosis  covers  the 
upper  three-fourths  of  the  muscle  and  from  its  inner  surface  many  fibers  take 
origin.  A  few  additional  fibers  arise  from  the  tendon  of  the  Gluteus  maximus, 
and  from  the  external  intermuscular  septum  between  the  Vastus  externus  and 
short  head  of  Biceps. 

Insertion. — (Plate  LXXIV.) — Into  patella. 

Action. — Extends  knee. 

Nerve  Supply. — Anterior  crural. 

Blood  Supply.  —  External  circumflex. 

Vastus  interims.— Description.  —  (Plates  LXIV-LXVIII-LXXIV.)  —If 
the  Rectus  is  reflected  a  narrow  space  is  seen  between  the  Vastus  interim-  and 
the  Crureus  extending  upward  from  the  inner  border  of  the  patella.  At  this 
space  they  can  lie  separated,  bin  they  arc  in  reality  one  muscle.  The  aponeuro- 
sis which  lies  on  the  deep  surface  of  the  muscle  receives  fibers  from  the  muscle, 
which  are  directed  downward  and  forward. 

Origin. — (Plate  XLVIII.) — Lower  one-half  of  anterior  intertrochanteric 
line,,  the  spiral  line,  the  inner  lip  of  the  linea  aspera,  the  upper  pari  of  the  in- 
ternal supracondylar  line,  and  the  tendon  of  the  Adductor  magnus  and  internal 
intermuscular  septum. 


138  ANATOMY    IN    A    NUTSHELL. 

Insertion.  -(Plate  LXXIV.) —  By  common  extensor  Tendon  into  the 
patella,  an  expansion  being  sent  to  capsule  of  knee-joint. 

A.<  i  ion.     Extends  leg  and  draws  patella  inward. 

N  i  i;\  e  Suppli  .     Branches  of  anterior  crural. 

Blood  Supply.     Femoral  artery. 

Crurcus.     Description. — Given  with  Vastus  internus. 

Origin.  (Plate  XLIX.)—  From  front  and  outer  aspect  of  shaft  of  femur 
in  its  upper  two-thirds  and  from  the  lower  part  of  the  external  intermuscular 
septum. 

Insertion.— (Plate  LXXIV.) — Its  fibers  end  in  a  superficial  aponeurosis 
which  forms  the  deep  part  of  the  Quadriceps  extensor  tendon. 

A.  tion.      Extends  leg  and  draws  patella  inward. 

Nerve  Si  pply.      Branches  of  anterior  crural. 

BLOOD  Si  PPLY. — Femoral  artery. 

Subcrureus.  Description. — This  muscle  may  consist  of  several  muscular 
bundles,  but  it  is  a  small  muscle.  It  is  most  always  distinct  from  the  Crureus, 
bu1  may  be  attached  to  it. 

<  Origin.      I  Plate  XLIV.) — Anterior  surface  of  lower  part  of  shaft  of  femur. 
I\-i  rtion.     (Plate  LXXIV.) — Upper  part  of  eul  de  sac  of  capsular  lig- 
ament. 

A<  tion.—  Lifts  capsule. 

\'i.k\  i.  Supply. — Branches  of  anterior  crural. 

BlOod  Supply. — Femoral  artery. 

Gracilis.— Description.— (Plates  LX1V-LXV1II-LXXIV.)— This  muscle 
is  broad  above,  narrow  below,  thin  and  flattened  as  a  whole.  Its  fibers  after 
passing  downward  end  in  a  rounded  tendon,  then  passes  behind  the  internal 
condyle  of  femur  to  curve  round  the  inner  tuberosity  of  the  tibia.  It  becomes 
flattened  before  its  insertion.  It  is  the  most  superficial  muscle  in  the  Internal 
Femora]  Region.  Its  tendon  which  is  just  above  that  of  the  Semitendinosus 
and  below  that  of  the  Sartorius  joins  the  latter.  It  is  separated  from  the  in- 
ternal lateral  ligament  of  the  knee-joint  by  a  synovial  bursa  which  is  common  to 
it  and  the  Semitendinosus. 

<  Origin.  I  Plate  X  F I II.) — Lower  half  of  margin  of  symphysis  and  anterior 
half  of  the  pubic  arch. 

Insertion.  (Plate  LI.)-  Upper  part  of  inner  surface  of  shaft  of  tibia  be- 
low the  tuberosity. 

A<  tion.     Assists  Sartorius  in  flexing  leg;  also  adducts  thigh. 

Nerve  Si  pply.     Third  and  fourth  lumbar  through  the  obturator  nerve. 

Blood  Si  pply.     Obturator  and  femoral  arteries. 

Pectineus.  Description.  (Plates  LXIV-LXVIII-LXXIV.)— This  mus- 
cle which  is  situated  at  the  anterior  part  of  the  upper  and  inner  aspect  of  the 
thigh  is  flat  and  quadrilateral. 

Origin.  (Plate  XLIII.)— (1)  Uio-pectineaJ  line;  (2)  surface  of  bone  in 
front  of  it  scia  covering  anterior  surface  of  muscle. 

Insertion.-  (Plate  XLVIII.)  Rough  line  between  lesser  trochanter  and 
lines  aspera. 


PLATE  XLVIII. 


OBTURATOR  EXTERNUS  (I). 


GUITEOUS  MEOIUS  (I). 


TUBERCLE  OF  THE 
OUADRATUS  FEMOfllS  (I) 


.VASTUS  EXTERNUS  (0) 


GLUTEAL  RIDGE. 
GLUTEUS  MAXIMUS  (I) 


LIGAMENTUM  TERES. 


POST    INTERTROCHANTERIC  LIKE. 
PSOAS  Jl). 


ADDUCTOR  MAGNUS  (I) 


OUTER  LIP  OF  LINE*  ASPERA. 
BICFJS  (0). 


VASTUS  EXTERNUS  (0). 


CRUREUS  (0) 


tXT.  SUPRA  CONDYLAR  LINE. 


POPUTEAI    SURFACE 


GASTROCNEMIUS  (0) 


ANT    CRUCIAL  LIGAMENT 


EXT   CONDYLE. 


INTERVENING  SPACE  OF  THE  LINEA  ASPER*. 

ADDUCTOR  LONGUS  (I). 


INNER  LIP  OF  LINEA  ASPERA. 


FOR  FEMORAL  ARTERY 

INT.  SUPRACONDYLAR  LINE. 
ADDUCTOR  MAGNUS  II). 

ADDUCTOR  TUBERCLE. 

GASTROCNEMIUS  (0). 

CAPSULl. 
INT    LATERAL  LIGAMENT. 


INTERCONDYLAR    NOTCH 


POST    CRUCIAL  LIGAMENT 


Posterior  View  of  Left  Femur. 
139 


140  ANATOMY    IN    A    NUTSHELL. 

Action.     Adducts  thigh. 

Nerve  Supply. — Anterior  crural,  obturator  accessory,  and  occasionally  a 
branch  from  the  obturator. 

Blood  Supply.—  Femoral  and  obturator  arteries. 

Adductor  Longus  —  Description.— ( Plates  LXIV-LXVIII-LXXI-LXXIV) 
—This  muscle  forms  the  inner  boundary  of  Scarpa's  triangle  and  is  the  most 
superficial  one  of  the  Adductors.  It  lies  on  the  same  plane  as  the  Pectineus. 
It  is  a  flat,  triangular  muscle. 

Origin. — (Plate  XL111.) — Front  of  OS  pubis,  at  junction  of  crest  with 
symphysis. 

Insertion. — (Plate  XLVIII.) — By  aponeurosis  into  linea  aspera. 

Action.     Adducts  thigh  powerfully. 

\'i  w\  r.  Supply. — Obturator. 

Blood  Supply. — Obturator  and  perforating  branches  of  profunda. 

Adductor  brevis.     1  Ascription.— (Plates  LXIV-LXVIII-LXXI-LXXIV.) 

The  Adductor  brevis,  which  is  somewhat  triangular,  is  situated  immediately 

beneath  the  Adductor  longus  and  the  Pectineus.     The  second  and  sometimes 

the  first  perforating  branches  of  the  profunda  femoris  artery  pierces  this  muscle 

near  it-  insertion. 

Origin. — (Plate  XLIII.) — Outer  surface  of  body  and  descending  ramus 
of  os  pubis,  between  Gracilis  and  Obturator  extern  us. 

Insertion. — (Plate  XLVIII.) — By  an  aponeurosis  into  lower  part  of  line 
Leading  from  the  lesser  trochanter  to  the  linea  aspera  and  the  upper  part  of  the 
same  line,  immediately  behind  the  Pectineus  and  upper  part  of  the  Adductor 
longus. 

A(  tion.  Assists  in  flexing  thigh  upon  pelvis;  also  in  drawing  leg  forward 
in  walking. 

\ki;\  i:  Supply. — Third  and  fourth  lumbar  through  the  obturator. 

Blood  Supply. — Obturator  and  perforating  branches  of  the  profunda. 


LESSON  XXXVII. 

Adductor  magnus.— Description.— (Plates  LXIV-LXVIII-LXXI-LXXIV.) 
—The  muscles  of  the  Anterior  Femoral  Region  are  separated  from  the  remain- 
ing muscles  of  the  Internal  Femoral  Region  by  the  Adductor  magnus. 
Along  the  attachment  of  this  muscle  there  are  three  and  sometimes  four  open- 
Lngs  Formed  by  tendinous  arches  attached  to  the  femur  for  the  passage  of  the 
three  perforating  branches  of  the  profunda  artery.  The  fourth  one,  when  pres- 
ent, is  for  the  terminal  branch  of  the  profunda. 

Origin. — (Plate  XLIII.) — (1)  Descending  ramus  of  os  pubis;  (2)  ascend- 
ing ramus  of  ischium ;(3)  outer  margin  of  under  surface  of  tuberosity  of  ischium. 
[nseri  con.  |  Plate  XLVIII.) — The  fibers  from  the  ramus  of  the  os  pubis 
are  vi'vy  short,  horizontal  in  direction,  and  are  inserted  into  the  rough  line  lead- 
ing from  the  greal  trochanter  to  the  linea  aspera,internal  to  the  Gluteus  max- 
Lmus;  those  from  the  ramus  of  the  ischium  are  directed  downward  and  outward 
to  be  inserted  by  mean-  of  a  broad  aponeurosis  into  the  linea  aspera  and  the 


ANATOMY    IN    A    NUTSHELL.  141 

upper  part  of  its  internal  prolongation  below.  The  internal  portion  of  the  mus- 
cle, consisting  principally  of  those  fibers  which  arise  from  the  tuberosity  of  the 
ischium,  forms  a  thick,  fleshy  mass,  descends  almost  vertically  and  terminates 
about  the  lower  third  of  the  thigh  in  a  rounded  tendon  which  is  inserted  into  the 
adductor  tubercle  on  the  inner  condyle  of  the  femur,  being  connected  by  a 
fibrous  expansion  to  the  line  leading  upward  from  the  tubercle  to  the  linea 
aspera. 

Action. — Adductor  of  thigh. 

Nerve  Supply.- — Obturator  and  branch  of  great  sciatic. 

Blood  Supply. — The  femoral  and  perforating  branches  of  profunda. 

Gluteus  maximus. — Description. — (Plate  LXV.) — This  muscle,  which  is 
made  up  of  fasciculi  lying  parallel  with  one  another,  is  very  coarse  in  structure. 
These  fasciculi  are  collected  together  into  large  bundles,  which  are  separated  by 
deep  cellular  intervals.  It  is  a  thick  and  quadrilateral  muscle  and  helps  to 
hold  the  trunk  erect.  It  is  the  most  superficial  muscle  in  the  Gluteal  Region. 
There  is  a  synovial  bursa  between  this  muscle  and  the  great  trochanter,  one 
between  its  tendon  and  the  Vastus  externus,  and  often  one  is  situated  on  the 
tuberosity  of  the  ischium. 

Origin. — (Plates  XLIII-XLV.) — (1)  Superior  curved  line  and  crest  of 
ilium;  (2)  posterior  surface  of  lower  part  of  sacrum;  (3)  side  of  coccyx;  (4) 
aponeurosis  of  Erector  spina?;  (5)  great  sacro-sciatic  ligament  and  fascia  cover- 
ing Gluteus  medius. 

Insertion. — (Plate  XLVIII.) — The  fibers  forming  the  upper  and  larger 
portion  of  the  muscle,  together  with  the  superficial  fibers  of  the  lower  portion, 
terminate  in  a  thick  tendinous  lamina,  which  passes  across  the  great  trochanter 
and  is  inserted  into  the  fascia  lata  covering  the  outer  side  of  the  thigh ;  the  deeper 
fibers  of  the  lower  portion  are  inserted  into  the  rough  line  leading  from  the  great 
trochanter  to  the  linea  aspera  between  the  Vastus  externus  and  Adductor  mag- 
nus. 

Action. — Extends,  adducts,  and  rotates  the  thigh  outward. 

Nerve  Supply. — Inferior  gluteal  and  small  sciatic. 

Blood  Supply. — Superior  and  inferior  gluteal. 

Gluteus  medius. — Description. — (Plate  LXV.) — The  posterior  border  of 
this  muscle  lies  parallel  with  the  Pyriformis  muscle  but  is  separated  from  it  by 
the  gluteal  vessels.  The  posterior  one-third  of  its  external  surface  lies  under  the 
Gluteus  maximus,  its  anterior  two-thirds  under  the  fascia  lata.  This  is  a  broad 
thick,  radiating  muscle  situated  on  the  outer  surface  of  the  ilium.  A  synovial 
bursa  is  situated  between  the  tendon  of  this  muscle  and  the  surface  of  the  great 
trochanter  in  front  of  its  insertion. 

Origin. — (Plates  XLIII-XLV.) — Outer  surface  of  ilium  between  superior 
and  middle  curved  lines;  (2)  crest  of  ilium;  (3)   fascia  covering  outer  surface. 

Insertion. — (Plate  XLIX.) — Oblique  line  of  great  trochanter. 

Action. — Adducts  the  extended  thigh,  rotates  same  and  supports  body 
on   limb. 

Nerve  Supply. — Superior  gluteal. 

Blood  Supply. — Superior  gluteal. 


PLATE  XLIX. 


OBTURATOR  INTERNUS  AND   GEMELLI  HI. 


GREATER  TROCHANTER. 

PTRIFORMIS  (I). 


-'»■■  <^''4Mi 

^  -    seck.  ■•ji  .",,>• ;ft\ 

CAPSULE  OF  "*"^^i^i    \*  ■i%<lttJ-'Jk,4 

„,,10INT     ATTACHED  TO  ANT.  INTER-      -  ^g^fl 

TROCHANTERIC  LINE.  JjgSft  j  I     'Aj?     I  M 

to! 


LESSEB  TROCHANTER 


1O0UCTOR  TUBERCLE. 
IOOUCTOR  MAGNUS  (I) 


CAPSULAR  LINE. 

INT   CONDYLE 


EXT   LATERAL  LKSAMEMT. 

POPLITEUS  (0). 
-     EXT    CONOTLE 


PATELLAR  FACET 

A.NTERIOR    VlKW    OF    LEFT    FEMUR. 


142 


ANATOMY    IN    A    NUTSHELL.  143 

Gluteus  minimus. — Description. — (Plate  LXV.) — This  muscle  is  situated 
immediately  beneath  the  Gluteus  medius.  It  is  the  smallest  of  the  three  Gluteal 
muscles.     There  is  a  synovial  bursa  between  its  tendon  and  the  great  trochanter. 

Origin. — (Plates  XLI1I-XLV.) — Outer  surface  of  ilium,  between  the  middle 
and  inferior  curved  lines,  and  from  the  margin  of  the  sacro-sciatic  notch. 

Insertion. — (Plate  XLVIII.) — Into  an  impression  on  anterior  border  of 
great  trochanter. 

Action. — Adducts  the  extended  thigh,  rotates  same  and  supports  body 
on  limb. 

Nerve  Supply. — Superior  gluteal. 

Blood  Supply. — Superior  gluteal  and  external  circumflex. 

Pyriformis. — Description. — (Plate  LXV.) — This  muscle  is  a  flat  pyra- 
midal one  situated  partly  within  the  pelvis  at  its  posterior  part  and  partly  at 
the  back  of  the  hip-joint.  It  lies  parallel  with  the  posterior  borderof  the  Glu- 
teus medius.  It  passes  out  of  the  pelvis  through  the  great  sacro-sciatic  foramen, 
thus  dividing  it  into  two  compartments.  The  superior  gluteal  nerve  and  the 
gluteal  vessels  leave  the  pelvis  above  this  muscle.  Below  this  muscle  the  in- 
ferior gluteal  nerve,  the  sciatic  vessels  and  nerves,  internal  pudic  vessels  and 
nerve,  and  nerves  to  the  Obturator  internus  and  the  Quadratus  femoris  leave 
the  pelvis. 

Origin. — (Plate  XLVI.) — Front  of  sacrum  by  three  fleshy  digitations  at- 
tached to  the  portions  of  the  bone  between  the  first,  second,  third  and  fourth 
anterior  sacral  foramina,  and  also  from  the  groove  leading  from  the  foramina; 
also  from  the  margin  of  the  great  sacro-sciatic  foramen,  and  from  the  anterior 
surface  of  the  great  sacro-sciatic  ligament. 

Insertion. — (Plate  XLIX.) — Upper  border  of  great  trochanter  behind, 
and  partly  blended  with,  the  tendon  of  the  Obturator  interims  and  (iemelli 
muscles. 

Action. — Draws  pelvis  forward  when  inclined  backward  and  assists  in 
steadying  it  upon  the  head  of  the  femur." 

Nerve  Supply. — First  and  second  sacral  nerves. 

Blood  Supply. — Sciatic. 

Obturator  internus. — Description. — (Plate  LXV.) — This  muscle,  like  the 
Pyriformis,  is  situated  partly  within  the  pelvis  and  partly  at  the  hack  of  the  hip- 
joint.  The  inner  surface  of  the  tuberosity  of  the  ischium  is  grooved  for  the  re- 
ception of  the  four  or  five  tendinous  bands  which  are  on  the  deep  surface  of  the 
muscle.  These  grooves  are  covered  with  cartilage  and  lined  by  a  synovia]  bursa. 
These  tendinous  bands  unite  into  a  flattened  tendon  which  passes  horizontally 
outward  to  its  insertion.  Between  the  capsular  ligament  of  the  hip  and  the 
tendon  of  this  muscle  is  a  bursa,  which  generally  communicates  with  the  bursa 
between  the  tendon  and  the  tuberosity  of  the  ischium,  the  two  bursa  making 
one  sac.     It  leaves  the  |   dvis  through  the  lesser  sacro-sciatic  foramen. 

Origin. — (PL-  e  XLIY.) —  From  the  inner  surface  of  anterior  and  external 
wall  of  pelvis.  it  surrounds  the  greater  part  of  the  obturator  foramen  being 

attached  to  the  'i  scending  ramus  of  the  os  pubis  and  ramus  of  ischium,  and  at 
theside  to  the  inner  surface  of  the  innominate  bone  below  andbehind  thepelvic 


144  ANATOMY    IN    A    NUTSHELL 

brim,  reaching  from  the  upper  part  of  the  great  sacro-sciatie  foramen  above  and 
behind  to  the  thyroid  foramen  below  and  in  front.  It  also  arises  from  the  inner 
surface  of  obturator  membrane  except  at  its  posterior  part,  from  the  tendinous 
arch  which  completes  the  canal  for  the  passage  of  the  obturator  vessels  and 
nerve,  and  to  a  slight  extent  from  the  obturator  layer  of  the  pelvic  fascia  which 
covers  it. 

Insertion. — (Plate  XLIX.) — Into  the  fore  part  of  the  inner  surface  of 
great  trochanter  in  front  of  obturator  externus,  together  with  the  Gemelli. 

Action.— Rotates  and  abducts  thigh. 

Nerve  Supply. — Fifth  lumbar,  first  and  second  sacral. 

Bi.<  >(  id  Supply.—  Sciatic 


LESSON  XXXVIII. 

Gemellus  superior. — Description. — (Plate  LXY.) — This  muscle  is  not 
always  present.  It  is  an  aid  to  the  Obturator  internus.  It  has  a  common  tendon 
with  the  Obturator  internus.     It  is  smaller  than  the  Gemellus  inferior. 

Origin. — (Plate  XLIY.) — Outer  surface  of  spine  of  ischium  and  blends 
with  tendon  of  Obturator  internus. 

I  nsertion. — (Plate  XLIX.)— Inner  surface  of  great  trochanter. 

A.<  tion. — Rotates  the  extended  thigh,  abducts  the  flexed  thigh. 

Nerve  Supply. — Fifth  lumbar,  first  and  second  sacral. 

Blood  Supply. — Sciatic  and  external  circumflex. 

Gemellus  inferior. — Description. — (Plate  LXY.) — This  muscle  is  larger 
than  the  Gemellus  superior  and  like  that  muscle  is  an  aid  to  the  Obturator  in- 
terims. 

Origin. — (Plate  LXIII.) — Upper  part  of  tuberosity  of  ischium  and  blends 
with  tendon  of  ( >bturator  internus  below. 

Insertion. — (Plate  XLIX.) — Inner  surface  of  great  trochanter. 

Action.     Rotates  extended  thigh,  abducts  flexed  thigh. 

\'u;\  e  Supply.—  Fourth  and  fifth  lumbar  and  first  sacral. 

Blood  Supply. — Sciatic  and  external  circumflex. 

Quadrat  us  femoris.—  1  )ks<ription. — (Plate  XLY.) — This  muscle  is  sit- 
uated between  the  upper  margin  of  the  Adductor  magnus  and  the  Gemellus  in- 
ferior. It  is  flat  and  quadrilateral.  The  terminal  branches  of  the  internal  cir- 
cumflex vessels  lie  between  the  Adductor  magnus  and  this  muscle. 

Origin.  (Plate  XLIII.) — Upper  part  of  external  lip  of  tuberosity  of 
ischium. 

Insertion.     (Plate  XLVIII.) — Quadrate  line  of  femur,  upper  part. 

A'  tion.-  Rotates  thigh  outward. 

Nerve  Supply.     Las1  lumbar  and  first  sacral. 

Blood  Si  pply.     Sciatic  and  internal  circumflex. 

Obturator  externus.  Description.-  (Plate  LXXI.) — The  deep  branches 
of  the  obturator  nerve  perforate  tins  muscle  while  the  superficial  ones  pass  above 
it.     The  obturator  vessels  lie  between  this  muscle  and  the  obturator  membrane. 


PLATE  L. 


POPLITEAL  NOTCH. 


EXTERNAL  FIBRO-CARTILAGE. 

POST.  CRUCIAL  LIGAMENT. 

CAPSULE. 

STYLOID  PROCESS. 

POST.  TIBIO-FIBULAR 
LIGAMENT 

,     SOLEUS  (0) 


'  Plexor  longus  hallucis  <o). 
flexor  surface  of  fibula 


NUTRIENT  FORAMEN 


'ERONEUS  BREVIS  (0).. 


INT.  FIBRO  CARTILAGE? 


XAPSUL'E. 

SEMIMEMBRANOSUS) 


POPLITEUS  (I). 

OBLIQUE  LINE. 
_SOLEUS  (0). 

NUTRIENT  FORAMEN. 


TIBIALIS  POSTICUS  (0). 
FLEXOR  LONGUS  DIGITORUM  (0). 


POST.  TIBIO-FIBULAR 
i  IGAMENT, 

EXT.  LATERAL  LIGAMENT. 
(POST.  FASCICULUS)' 
EXT.  LATERAL  LIGAMENT 
(MIDDLE  FASCICULUsT 


GROOVE  FOR  TIBIALIS  POSTICUS  AND  FLEXOR' 
LONGUS  DIGITORUM 


NT.  LATERAL  LIGAMENT. 


POST.  LIGAMENT  OF  ANKLE  JOINT. 


GROOVE  FOR  FLEXOR  LONGUS  HALLUCIS. 

Postkkiok  View  of  Left  Tibia  and   Fibula. 


145 


146  ANATOMY  IN  A   NUTSHELL. 

This  muscle,  which  covers  the  outer  surface  of  the  anterior  wall  of  the  pelvis, 
Ls  flat  and  triangular. 

Origin.     (Plate    XL1II.) — (1)  Margin   of   inner   boundary   of   obturator 

foramen:  (2)   inner  two-thirds  of  outer  surface  of  obturator  membrane;  (3)   ten- 
dinous arch  of  obturator  canal. 

Insertion.     (Plate  XLVIII.) — Digital  fossa  of  femur. 

ACTION.-  Rotates  thigh  outward  and  assists  in  holding  head  of  femur  in 
place. 

\  i.i;\  i.  Supply.     Second,  third,  and  fourth  lumbar  through  obturator. 

Blood  Supply. — Obturator  and  femoral. 

Weeps. —  Description. — (Plate  LXY.) — This  muscle- — Biceps  flexor 
cruris-  is  situated  on  the  posterior  and  outer  aspect  of  the  thigh.  It  is  quite 
large  and  its  tendon  forms  the  outer  hamstring.  The  tendons  of  the  Semi- 
membranosus, Semitendinosus,  Gracilis  and  Sartorius  form  the  inner  hamstring, 
and  lie  to  the  inner  side  of  the  knee-joint. 

Origin. — (Plate  XLIII.) — By  two  heads;  the  long  head  from  the  lower 
and  inner  impression  on  the  back  part  of  the  tuberosity  of  the  ischium,  by  a 
tendon  common  to  it  and  the  Semitendinosus,  and  from  the  lower  part  of  the 
greal  sacro-sciatic  ligament.  The  femoral,  or  short  head,  from  the  outer  lip 
of  the  linea  aspera,  between  the  Adductor  magnus  and  Vastus  externus,  ex- 
tending almost  as  high  as  the  insertion  of  the  Gluteus  maximus;  also  from  the 
outer  prolongation  of  the  linea  aspera  to  within  two  inches  of  the  outer  condyle, 
and  from  the  external  intermuscular  septum. 

Insertion. — (Plate  LI.) — The  fibers  of  the  long  head  form  a  fusiform  belly, 
which,  pnssing  obliquely  downward  and  a  little  outward,  terminates  in  an 
aponeurosis  which  covers  the  posterior  surface  of  the  muscle  and  receives  the 
fibers  of  the  short  head;  this  aponeurosis  becomes  gradually  contracted  into  a 
tendon  which  is  inserted  into  the  outer  side  of  head  of  fibula,  and  by  a  small  slip 
into  lateral  surface  of  external  tuberosity  of  tibia. 

A.CTION.      Ilexes  leg  on  thigh;  rotates  semi-flexed  knee  outward. 

Nerve  Supply. — First,  second,  and  third  sacral  through  the  great  sciatic. 

Blood  Supply.      Perforating  branches  of  the  profunda. 

Semitendinosus.  DESCRIPTION. — (Plate  LXY.) — This  muscle  is  situated 
at  the  posterior  and  inner  aspect  of  the  thigh.  It  has  a  remarkably  long  tendon, 
which  lies  behind  the  Sartorius.  and  below  that  of  the  Gracilis  to  which  it  is 
joined.  Its  tendon  is  separated  from  the  internal  lateral  ligament  of  the  knee- 
joint  by  a  bursa.  About  the  middle  of  the  muscle  there  is  generally  a  tendi- 
nous intersection. 

Origin.  (Plate  XLIII.)  From  the  lower  and  inner  impression  on  tuber- 
osity of  ischim  by  tendon  common  to  it  and  the  long  head  of  Biceps;  also  from 
aponeurosis  which  connect-  the  adjacent  surface  of  the  two  muscles  to  the  ex- 
tent of  about  three  inches  a  ft  ei-  their  origin. 

[N8ERTION.  (Plate  LI.)  It  form-  ;i  fusiform  muscle  which,  passing  down- 
ward and  inward,  terminates  ;i  little  below  the  middle  of  the  thigh  in  a  long, 
round  tendon  which  li<  s  along  the  inner  side  of  the  popliteal  space,  then  curves 
around  the  inner  tuberosity  of  the  tibia  and  is  inserted  into  the  upper  part  so 


ANATOMY    IN    A    NUTSHELL.  147 

the  inner  surface  of  shaft  of  that  bone.  At  its  insertion  it  gives  off  a  prolonga- 
tion to  the  deep  fascia  of  the  leg. 

Action. — Flexes  leg  on  thigh  and  rotates  it  inward. 

Nerve  Supply. — First,  second,  and  third  sacral  through  great  sciatic. 

Blood  Supply. — Perforating  branches  of  the  profunda. 

Semimembranosus. — Description. — (Plate  LXY.) — This  muscle  is  mem- 
branous above  and  muscular  below.  It  is  situated  at  the  back  part  and  inner 
side  of  the  thigh.  At  its  origin  the  aponeurosis  covers  the  upper  and  anterior 
part  of  the  muscle,  and  from  this  aponeurosis  muscular  fibers  arise  and  con- 
verge to  another  aponeurosis  which  covers  the  lower  part  of  its  posterior  sur- 
face and  contract  into  the  tendon  of  insertion. 

Origin. — (Plate  XLIII.) — By  thick  tendon  from  upper  and  outer  impress- 
sion  on  back  part  of  tuberosity  of  ischium  above  and  to  the  outer  side  of  the 
Biceps  and  Semitendinosus. 

Insertion. — (Plate  L.) — Groove  on  inner  and  back  part  of  inner  tuber- 
osity of  tibia,  beneath  the  internal  lateral  ligament.  At  its  insertion  fibrous 
expansions  are  given  off;  one  of  these,  of  considerable  size,  passes  upward  and 
outward  to  be  inserted  into  the  back  part  of  outer  condyle  of  femur,  forming 
part  of  posterior  ligament  of  knee-joint;  a  second  is  continued  downward  to  the 
fascia  which  covers  the  Popliteus  muscle.  The  tendon  also  sends  a  few  fibers 
to  join  the  internal  lateral  ligament. 

Action. — Flexes  leg  and  rotates  it  inward. 

Nerve  Supply. — Pdrst.  second  and  third  sacral  through  the  great  sciatic. 

Blood  Supply. — Perforating  branches  of  the  profunda. 


LESSON  XXXIX. 

Femur. 

The  femur  (Plates  XLYIII-XLIX)  is  about  one-fourth  the  length  of  the 
body  and  is  the  longest  and  strongest  as  well  as  the  largest  bone  in  the  body. 
When  one  is  standing  it  inclines  inward  and  a  little  backward.  The  main  part 
is  the  shaft  or  diaphysis.  Its  upper  part  has  a  head,  neck,  a  greater  tro- 
chanter, and  a  LESSER  TROCHANTER.  Its  lower  part  is  expanded  into  TWO 
CONDYLES — an  external  one  and  an  internal  one.  Above  each  one  of  these  is  a 
SUPRACONDYLAR  LINK. 

The  neck  makes  an  angle  of  12.")  degrees  with  the  diaphysis.  It  i>  directed 
upward. inward  and  a  little  forward, bein^  broad  and  compressed  at  the  base  Inn 
becomes  rounded  at  its  junction  with  the  head.  It  is  longer  below  and  behind 
than  above  and  in  front.  Posteriorly  and  above  where  it  joins  the  greater  tr<  - 
chanter  is  a  depression  (digital  fossa)  for  the  insertion  of  the  Obturator  exter- 
nals. Where  it  joins  the  shaft  between  the  two  trochanters  is  tile  POSTERIOR 
INTERTROCHANTERIC  LINE.  About  half  an  inch  above  this  line  the  capsular  lig- 
ainent  of  the  hip-joint   is  attached  to  the  neck. 

The  bead  is  an  expanded  portion  of  the  neck,  and  forms  more  than  a  hem- 
isphere.    It   articulates  witli   the  acetabulum  of  the  innominate   bone.     The 

Fossa   CAPITIS   is  a   depression   a   little   below  and   behind    the  center  of   the   head. 


P  LATE  LI. 


INT.  FIBRO  CARTILAGE. 


CORONARY  LIGAMENT 
ANT.  CRUCIAL  LIGAMENT 


SPINE. 


EXTERNAL  FIBRO-CARTILAGE. 
CAPSULE. 


INNER  TUBEROSITY.   K»A<  \ 


INT.  LATERAL  LIGAMENT 


LIGAMENTUM  PATELLAE  (l); 
(QUADRICEPS  EXTENSOR). 


GRACILIS  (I) 
SARTORIUS  (ij 


SEMI-TENDINOSUS(/ 

EXT.  SURFACE  OF  TIBIA. 
TIBIALIS  ANTICUS  (0) 


ANT.  BORDEROR  CREST  OF  TIBIA 


INT.  SURFACE  OF  TIBIA. 


INTEROSSEOUS  MEMBRANE 


ANT.  LICAMENT  OF  ANKLE  JOINT. 
INT.  LATERAL  LIGAMENT 
INTERNAL  MALLEOLUS. 


OUTER  TUBEROSITY. 
).  BICEPS  AND  ANT. 
TIBIO-FIBULAR  LIGAMENT. 

EXT.  LATERAL  LIGAMENT. 


EXTENSOR  LONGUS  WGITORUM  (0), 


PERONEUS  LONGUS  (0). 


EXTENSOR  LONGUS  DIGITORUM  (0), 

PFRONEAL  SURFACF  flF  FIBULA 

EXTENSOR  SURFACE  Of  FIBULA 

'. EXTENSOR  PROPRIUS  HALLUCIS  (0; 

PERONEUS  BREVIS<0). 


FIBULA. 
-  PERONEUS  TERTIUS  (0). 


-  SUBCUTANEUS  PORTION. 


ANT.  TIBIO-FIBULAR  LIGAMENT. 


EXTERNAL  MALLEOUS. 


EXTERNAL  LATERAL. LIGAMENT. 
(ANT.  FASCICULUS). 


Anterior  View  of  Left  Tibia  and  Fibula. 
148 


ANATOMY    IN    A    NUTSHELL.  149 

The  fore  part  of  this  depression  gives  attachment  to  the  ligamentum  teres  of 
the  hip-joint.     The  fossa  capitis  has  one  or  two  vascular  foramina. 

The  greater  trochanter  is  an  expanded  portion  of  the  upper  part  of  the  bone 
opposite  the  head,  its  upper  limit  being  about  half  or  two-thirds  of  an  inch  below 
the  upper  limit  of  the  head.  The  word  trochanter  means,  to  turn.  The 
Gluteus  minimus  is  attached  to  its  anterior  surface  in  a  broad  depression. 
The  Gluteus  medius  is  attached  to  ax  oblique  link,  which  runs  downward  and 
forward  from  the  posterior  aspect  of  its  upper  border.  On  the  anterior  surface 
of  the  greater  trochanter  is  the  superior  cervical  tubercle  of  the  femur. 
which  marks  the  JUNCTION  of  the  following  muscles:  Vastus  externus.  Gluteus 
minimus.  Obturator  interims,  and  the  two  Gemelli.  Above  and  external  to 
the  insertion  of  the  Obturator  interims  and  the  Gemelli  is  the  INSERTION  of  the 
Pyriformis.  About  the  center  of  the  posterior  intertrochanteric  line  is  the 
tubercle  of  the  Quadratus  femoris.  The  linea  quadkati,  when  present, 
passes  vertically  down  from  this  tubercle. 

The  lesser  trochanter  is  a  pyramidal  projection  at  the  junction  of  the  lower 
part  of  the  posterior  intertrochanteric  line  and  the  diaphysis.  Its  direction 
is  inward  and  backward,  and  its  apex  gives  attachment  to  the  Ilio-psoas  muscle. 

In  front  the  neck  is  separated  from  the  shaft  by  the  anterior  intertro- 
chanteric line,  which  is  the  upper  part  of  the  spiral  line.  This  line  commences 
at  the  tubercle  of  the  femur,  and  runs  down  in  front  of  the  lesser  trochanter. 
It  gives  attachment  to  the  capsular  ligament  and  the  Vastus  interims  and  Cru- 
reus  muscles. 

The  shaft  is  arched  forward;  its  middle  is  somewhat  cylinderical,  but  below 
it  is  expanded.  It  has  an  anterior  and  two  lateral  surfaces  which  are  not  sep- 
arated by  well  defined  lines.  The  two  Yasti  and  the  Crureus  muscles  cover 
these  surfaces.  The  linea  aspera  separates  the  two  surfaces  posteriorly.  This 
line  is  well  marked  in  the  middle  third  of  the  thigh,  bifurcating  both  above  and 
below.  Of  its  two  upper  divisions  the  external  one  extends  to  the  greater  tro- 
chanter making  the  gluteal  ridge  for  the  attachment  of  the  Gluteus  maximus. 
The  internal  division  winds  around  below  the  lesser  trochanter,  passing  into  the 
anterior  intertrochanteric  line,  and  forming  the  lower  part  of  the  spiral  line. 
Another  line  passes  from  this  line  to  the  lesser  trochanter  for  the  attachment 
of  the  Pect  incus. 

Below  the  linea  aspera  divides  into  two  lines  which  extend  to  the  two 
condyles,  thus  forming  the  supracondylar  lines,  which  enclose  the  popliteal  sur- 
face of  the  femur.  The  inner  line  ends  at  the  Adductor  tubercle,  ami  i-  broken 
above  this  where  the  femoral  vessels  lie  on  the  bone.  Above  the  middle  of  the 
linea  aspera  is  a  NUTRIENT  foramen,  which  is  directed  from  the  knee.  (Page 
P.).)      A  SECOND  foramen  inav  exist  nearer  the  distal  end  of  the  bone. 

The  inner  lip  of  the  linea  aspera  gives  attachment  to  the  Vasius  interims, 
and  the  outer  lip  gives  attachment  to  the  Vastus  externus.  The  Adductor 
magnus  is  attached  between  the  two.  Between  the  Adductor  magnus  ami  the 
Vastus  externus  are  the  Gluteus  maximus  and  the  short  head  of  the  Biceps. 
Between  the  Adductor  magnus  and  the  Vastus  internus  are  the  Qiacus,  Pecti 
neus,  Adductor  brevis,  and  Adductor  Longus.     At  the  lower  pari  of  the  poplitea 


150  ANATOMY    IN    A    NUTSHELL. 

space  above  each  condyle  is  the  origin  of  one  head  of  the  Gastrocnemius. 
The  distal  extremity  has  two  condyles,  which  are  united  anteriorly  but 
separated  posteriorly  by  the  intercondylar  notch.  The  external  condyle 
is  broader  and  more  prominenl  anteriorly,  while  the  internal  one  is  more 
prominent  internally,  and  it  extends  to  a  lower  level,  when  the  femur  is  taken 
from  the  body.  When  the  femur  articulates  with  the  tibia  the  two  condyles 
.,,,.  (l|1  the  -mum'  level.  Both  condyles  are  convex  for  the  articulation  of  the 
tibia,  and  between  these  two  anteriorly  is  a  concave  strface  for  the  articula- 
tion of  the  patella.  The  patellar  surface  has  a  vertical  hollow  and  two  lips. 
The  external  portion  which  is  wider  and  more  prominent  than  the  internal  por- 
tion rises  higher.  The  tibial  surfaces  are  almost  parallel  being  a  little  closer 
anteriorly  than  posteriorly.  The  lateral  surface  of  each  condyle  extends  into 
:i  tuberosity  or  epicondyle,  which  gives  attachments  to  ligaments.  Above  the 
external  condyle  is  a  depression  for  the  outer  head  of  the  Gastrocnemius.  The 
inner  head  of  the  <  hisirocnenhns  arises  from  the  upper  part  of  the  inner  condyle. 
The  [ntercondyleae  fossa  has  two  depressions  for  the  crucial  ligaments. 
The  ONE  FOE  tin.  wtkkiok  ligament  is  on  the  posterior  part  of  the  inner  sur- 
face of  thf  external  condyle.  The  one  for  the  posterior  ligament  is  on  the 
anterior  part  of  the  external  surface  of  the  inner  condyle.  The  angle  of  the 
neck  of  femur  with  the  shaft  makes  no  changes  after  growth  is  completed. 

Blood  Supply. — The  head  and  neck  of  the  femur  receive  branches  from 
the  sciatic,  obturator  and  circumflex  arteries.  The  trochanter  receives  twigs 
from  the  circumflex  arteries.  The  nutrient  vessel  for  the  shaft  is  derived  from 
second  perforating;  it  enters  near  the  linea  aspera  and  is  directed  towards  the 
head  of  the  bone.  Condyles  are  nourished  by  articular  branches  from  the 
popliteal  and  the  anastomotic  of  femoral. 

Ossifk  \'i ION. -  From  five  centers.  The  one  for  the  shaft  is  a  primary 
center  and  begins  to  ossify  in  the  seventh  week  of  intra-uterine  life.  The 
other  four  are  epiphyseal  centers.  The  one  for  the  lower  extremity  appears  in 
the  NINTH  MONTH  and  joins  the  bone  in  the  twentieth  year.  This  is  the  only 
epiphysis  which  ossifies  before  birth, although  some  observers  say  the  proxifhal 
end  of  the  tibia  ossifies  before  birth.  The  one  for  the  head  appears  in  the  first 
yi.ai;  and  joins  the  bone  in  the  nineteenth  year.  The  one  for  the  greater  tro- 
chanter appears  the  fourth   yi.ai;  and  joins  the  bone  in  the  eighteenth  year. 

The  •  for  the  lesser  trochanter  appears  in  the  thirteenth  or  fourteenth 

i  eab  and  join-  the  bone  the  seventeenth  year. 

Articulates.-  With  three  bones:  os  innominatum,  tibia  and  patella. 
\ii  M  HMENT  "i  MuS(  LES. — Twenty-three.  To  the  great  trochanter,  the 
Gluteus  medius,  Gluteus  minimus,  Pyriformis,  Obturator  externus.  Obturator 
interim.-.  Gemellus  superior,  Gemellus  inferior,  and  Quadratus  femoris.  To 
the  lesser  trochanter,  the  Psoas  magnus  and  the  Iliacus  below  it.  To  the  shaft, 
tin'  Vastus  externus,  Gluteus  maximus,  short  head  of  Biceps,  Vastus  internus, 
Adductor  magnus,  Pectineus,  Adductor  brevis,  Adductor  longus,  Crureus  and 
Subcrureus.     To  the  condyles,  the  Gastrocnemius,  Plantaris  and  Popliteus. 


PLATE  LI  I. 


EXTENSOR  LONGUS  DIGITOfillM  (1) 


EXTENSOR  LONGUS  HALLUCIS  (1). 


THIRD  PHALANX   -H  fl 
SECOND  PHALANX 

FIRST  PHALANX 


EXTENSOR 
BficViS  DIGITORUM  (0) 


TENDO  ACHILLIS. 


Dorsum  of  Left  Foot. 
151 


152  ANATOMY    IN    A    NUTSHELL. 


LESSON  XL. 


Tibialis  anticus. — Description. — (Plate  LXXV.) — The  anterior  tibial 
vessels  and  nerve  run  along  the  outer  border  of  this  muscle,  which  is  just  be- 
neath the  fascia  on  the  outer  side  of  the  tibia.  It  is  thick  and  fleshy  above,  but 
tendinous  below  where  it  passes  through  the  innermost  compartment  of  the 
anterior  annular  ligament. 

Origin.  (Plate  LI.) — (1)  Outer  tuberosity  of  tibia;  (2)  upper  two-thirds 
of  shafl  of  tibia;  (•">)  interosseous  membrane  adjoining;  (4)  deep  surface  of 
fascia;  (5)  intermuscular  septum. 

Insertion. — (Plate  LIII). — Inner  and  under  surface  of  internal  cuneiform 
bone  and  base  of  metatarsal  of  great  toe. 

Action.     Flexes  tarsus  upon  leg  and  assists  in  inverting  the  foot. 

Nerve  Supply. — Fourth  and  fifth  lumbar  and  first  sacral  through  anterior 
tibial. 

Blood  Supply. — Anterior  tibial  artery. 

Extensor  propius  hallucls. — Description. — (Plate  LXXV.) — This  muscle 
lies  between  the  Tibialis  amicus  and  Extensor  longus  digitorum.  It  is  a  thin, 
Hat  muscle  and  hs  tendon  occupies  its  anterior  border  below.  This  tendon 
passes  through  a  distinct  compartment  in  the  lower  portion  of  the  annular  lig- 
ament, it  also  crosses  the  anterior  tibial  vessels  near  the  ankle-joint  and  then 
lies  on  the  inner  side  of  these  vessels.  It  gives  a  thin  prolongation  on  each  side 
of  the  metatarso-phalangeal  articulation,  which  covers  the  surface  of  the  joint. 

Origin.-  -(Plate  LI.) — (1)  Anterior  surface  of  fibula,  middle  two-fourths 
of  same;  (2)   part  of  interosseous  membrane. 

Insertion. — (Plate  I.I  I.) — Base  of  last  phalanx  of  great  toe.  It  usually 
sends  an  expansion  from  the  inner  side  of  the  tendon  to  be  inserted  into  base  of 
6rs1    phalanx. 

Action.— Extends  great  toe  and  flexes  tarsus. 

\'i.i;\  i:  Supply.— Fourth  and  fifth  lumbar  and  first  sacral  through  anterior 
tibial. 

Blood  Supply.— Anterior  tibial. 

Extensor  Longus  digitorum.— Description.— (Plate  LXXV.) — This  muscle 
lies  external  to  the  other  muscles  in  this  region.  It  is  enlongated  and  flat- 
tened. It  and  the  Peroneus  tertius  enter  the  same  canal  in  annular  ligament. 
It  divides  into  four  slip-,  one  for  each  of  the  four  inner  toes.  A  tendon  from 
the  Extensor  brevis  digitorum  join-  the  three  inner  of  these  tendons  on  their 
outer  side  opposite  the  metatarso-phalangeal  articulation.  All  four  slips  re- 
ceive fibrous  expansions  from  the  Interossei  and  Lumbricales,  after  which  they 
spread  out  into  a  broad  aponeurosis  which  covers  the  dorsal  surface  of  the  first 
phalanx.  This  aponeursosis  divides  Into  three  slips  at  the  articulation  of  the 
first    with   the  second  phalanx. 

Origin.— (Plate  LI.)  (1)  Outer  tuberosity  of  tibia;  (2)  upper  three- 
fourths  of  anterior  surface  of  shafl  of  fibula;  (3)  interosseous  membrane;  (4) 
deep  surface  of  Fascia;  (5)   intermuscular  septa. 


ANATOMY    IN    A    NUTSHELL.  153 

Insertion. — (Plate  LII.) — The  middle  slip  is  Inserted  into  the  base  of  the 
second  phalanx:  the  two  lateral  slips,  after  uniting  on  the  dorsal  surface  of  the 

second  phalanx,  are  continued  onward  and  inserted  into  base  of  the  third. 

Action. — Extends  toes  and  flexes  foot. 

Nekve  Supply. — Fourth  and  fifth  lumbar  and  first  sacral  through  anterior 
tibial. 

Blood  Supply. — Anterior  tibial. 

Peroneus  tertius. — Description. — (Plate  LXXV.) — This  muscle  is  some- 
times wanting. sometimes  it  is  described  as  a  fifth  tendon  of  the  Extensor  longus 
digitorum  with  which  it  is  joined,  and  their  tendons  pass  through  the  same 
canal  in  the  anterior  annular  ligament. 

Origin. — (Plate  LI.) — (1)  Lower  fourth  of  anterior  surface  of  fibula;    2 
lower  part  of  interosseous  membrane:  (o)   intermuscular  septum. 

Insertion. — (Plate  LII.) — Inner  side  of  dorsal  surface  at  base  of  meta- 
tarsal of  little  toe. 

Action. — Flexes  and  everts  foot. 

Nerve  Supply. — Fourth  and  fifth  lumbar  and  first  sacral  through  anterior 
tibial. 

Blood  Supply. — Anterior  tibial. 

Gastrocnemius. — Description. — (Plate  LXXVII.) — The  Gastrocnemius 
has  two  heads  the  inner  of  which  is  the  larger.  This  muscle  forms  the  greater 
part  of  the  calf  of  the  leg  and  is  the  most  superficial  one  in  this  region.  An 
aponeurosis  spreads  out  from  each  tendon  to  cover  the  posterior  part  of  that 
portion  of  the  muscle  to  which  it  belongs.  The  muscular  fibers  of  the  outer 
head  are  thinner  and  do  not  extend  as  low  as  those  of  the  inner.  Muscular 
fibers  are  given  off  from  the  anterior  surface  of  these  tendinous  expansions. 
This  muscle  gradually  gets  smaller  and  its  tendon  with  that  of  the  Soleus  forms 
the  tendo  Achillis.  In  the  tendon  of  the  outer  head  there  is  a  sesamoid 
fibro-cartilage  (very  seldom  osseous):  and  one  is  occasionally  found  in  the  ten- 
don of  the  inner  head. 

Origin. — (Plate  L.) — Inner  and  larger  head  from  depression  at  upper  and 
back  part  of  inner  condyle  and  from  adjacent  part  of  femur.  The  outer  head 
from  impression  on  outer  side  of  external  condyle  and  from  posterior  surface  oi 
femur  immediately  above  the  condyle.  Both  heads  also  arise  by  a  few  fibers 
from  the  ridges  which  are  continued  upward  from  the  condyle-  to  the  linea  a-- 
pera. 

Insertion. — (Plate  LII.) — Os  calcis  by  tendo  Achillis. 

Actiox.  —  Extends  foot  and  flexes  leg. 

Nerve  Supply. — First  and  second  sacral  through  internal  popliteal  (from 
greal  sciatic.) 

Blood  Supply. — Popliteal. 

Soleus. — Description.— (Plate  LXXVII.)— Situated  beneath  the  Gastro- 
cnemius is  the  Soldi-,  which  i>  a  broad  flat  muscle.  In  shape  it  resembles  a 
sole  fish,  hence  its  name.  The  deep  transverse  fascia  of  the  leg,  separates 
this  mucle  from  the  posterior  vessels  and  nerve.  A-  -aid  before  the  tendon  of 
this  muscle  and  that  of  the  Gastrocnemius  make  the  tendo  Achillis. 


154  ANATOMY    IS    A    NUTSHELL. 

Origin. — (Plato  L.) — (1)  Back  part  of  head  of  fibula ;  (2)  upper  'hird  of 

rior  surface  of  shaft  of  fibula;  (3)  oblique  line  of  tibia;  (4)  middle  third  of 
internal  border  of  tibia;  (5)  tendinous  arch  between  the  tibial  and  fibular  ori- 
gin-, beneath  which  the  popliteal  vessels  and  internal  popliteal  nerve  pass. 

[nsertion.— (Plate  LII.) — Os  calcis  by  tendo  Achillis. 

A*  HON.—  Steadies  leg  on  foot  :  prevents  body  from  falling. 

N  era  i.  Suppli  .      Internal  popliteal  and  posterior  tibial. 

'u.oDi)  Supply. — Popliteal. 

Plantaris.-  Description. — (Plate  LXXVII.) — This  muscle  is  sometimes 
absent  and  again  it  may  be  double.  It  has  the  longest  tendon  of  any  muscle 
in  the  body.  It  takes  its  name  because  it  is  sometimes  inserted  into  the  plantar 
fascia.  The  muscular  part  of  the  Plantaris  is  a  small  fusiform  belly  about  three 
or  four  inches  in  length.  It  is  situated  between  the  Gastrocnemius  and  Soleus 
and  the  tendon  finally  running  along  the  inner  side  of  the  tendo  Achillis.  It 
may  be  lost  in  the  fascia  of  the  leg  or  the  internal  annular  ligaments. 

Origin. — (Plate  XLVIII.) — From  the  lower  part  of  outer  prolongation  of 
linea  aspera  and  from  posterior  ligament  of  knee-joint. 

Insertion. — (Plate  LII.) — Os  calcis  with  tendo  Achillis. 

Action. — Flexes  leu-  and  extends  foot. 

Nerve  Supply. — Internal  popliteal. 

Blood  Supply. — Popliteal. 


LESSON  XLI. 

Popliteus.— Description. — (Plate  LXXIX.) — This  muscle  forms  part  of 
the  popliteal  space.  It  is  a  thin  flat  triangular  muscle,  and  is  different  from 
nio-t  other  muscles  in  that  its  origin  is  smaller  than  its  insertion.  The  internal 
popliteal  nerve  and  the  popliteal  vessels  cross  the  superficial  surface  of  this 
muscle. 

Origin. — (Plate  XLIX.) — Deep  depression  on  outer  condyle  of  femur  and 
posterior  ligament  of  knee. 

Insertion.-  (Plate  L.) — Inner  two-thirds  of  triangular  surface  above 
oblique  line  on  posterior  surface  of  shaft  of  tibia  ami  tendinous  expansion  cover- 
ing surface  of  muscle. 

Action.     Flexes  and  rotates  leg  inward. 

Xi:i;\  i;  Supply.-  fourth  and  fifth  lumbar  and  first  sacral  through  internal 
popliteal. 

Blood  Suppli  .  -  Popliteal. 

Flexor  longua  hallucis. — Description. — (Plate  LXXIX.) — This  musch/is 
on  the  fibular  side  of  the  lei:  although  it  passes  to  the  great  toe.  Its  tendon 
occupies  most  all  of  the  posterior  surface  of  the  muscle,  then  it  passes  through 
three  grooves  in  three  different  bono,  first  one  is  on  the  posterior  surface  of 
the  lower  end  of  the  tibia;  the  second  one  is  on  the  posterior  surface  of  the 
astragalus;  and  the  third  one  is  beneath  the  sustentaculum  tali  of  the  os  calcis. 
The  tendon  finally  passes  between  the  two  heads  of  the  Flexor  brevis  hallucis 
to  its  insertion. 


PLATE  LIU. 


FLEXCI*  L8NGUS  HALLUCIS      <1). 


ktf)  FLEXOR  LONGUS  DIGITORUM  (I). 


4DQUCT0«  H»LLUCIS 


ELEXOR  BREVIS 
HaLLUCISMi 
'OUTER  PORTION! 
(INNER  PORTION 


ABDUCTOR  HALLUCIS  (l/      V1 


PERONEUS      LONGUS      H) 


TIBIALIS  AUTICUS  (1 


TIBIALIS  POSTICUS  (1) 


ACCESSORIUS  (INNER  HEAD) 

FLEXOR  BREVIS  DIGITORUM  (0) 
ABDUCTOR  HALLUCIS  \0) 


LANTAR  INTEROSSEOUS  (1). 


ABDUCTOR 

WIN  I  Ml  DIGITI  (1) 
FLEXOR  BREVIS 


NTAR  INTEROSSEOUS  (0). 


DDUCTOR  HALLUCIS  (0). 


_FLEXOR  BREVIS 
MINIMI  DIGITI  (0) 


FLEXOR  BREVIS  HALLUCIS     (0) 


ACCESSORIUS  (OUTER  HEAD)  (0) 


ABDUCTOR  MINIMI  DlGlTl  ,0| 


POSTERO— INFERIOR  SURFACE  OF  THE  CALCANEUM. 


Plantar  Surface  of  Left  Foot. 
155 


156  ANATOMY    IN    A    NUTSHELL. 

Origin.— (Plate  L.) — (1)  Lower  two-thirds  of  posterior  surface  of  shaft 
of  fibula  except  an  inch  at  lowest  part:  (2)  lower  part  of  interosseous  mem- 
brane; (3)   intermuscular  septum;  (4)  fascia  covering  Tibialis  posticus. 

Insertion. — (Plate  LIII.)     Base  of  last  phalanx  of  great  toe. 

Action.     Flexes  ureal  toe  and  extends  foot. 

Nerve  Supply.  Fifth  lumbar  and  first  and  second  sacral  through  pos- 
terior tibial. 

Blood  Supply.  —  Posterior  tibial. 

Flexor  Longus  digitorum.— Description. — (Plate  LXXIX.) — This  muscle 
is  small  at  its  origin  but  gradually  increases  in  size  as  it  descends.  Its  tendon 
occupies  nearly  all  of  the  posterior  surface  of  the  muscle.  The  tendons  of  the 
Tibialis  posticus  and  this  muscle  pass  through  a  common  groove  behind  the 
internal  malleolus,  but  each  tendon  has  its  own  synovial  sheath.  They  are 
separated  from  each  other  by  a  fibrous  septum.  As  the  tendon  crosses  the  sole 
of  the  foot  obliquely  forward  and  outward,  it  divides  into  four  tendons  each  of 
which  passes  through  the  tendons  of  the  Flexor  brevis  digitorum  opposite  the 
base  of  the  first  phalanx.  Just  before  it  divides  it  is  joined  by  the  Flexor  ac- 
cessories. 

Origin.-  -(Piatt1  L.)  —  Posterior  surface  of  shaft  of  tibia,  immediately  below 
i  lie  oblique  line  to  within  three  inches  of  its  extremity  internal  to  the  tibial 
origin  of  the  Tibialis  posticus. 

Insertion. — (Plate  LIII.)  —  Into  bases  of  last  phalanges  of  the  four  lesser 
toes. 

A.CTION. —  Flexes  toes  and  extends  foot. 

Nerve  Supply. — Fifth  lumbar  and  first  sacral  through  posterior  tibial. 

Blood  Supply. — Posterior  tibial. 

Tibialis  posticus. — Description. — (Plate  LXXIX.) — This  muscle  is  the 
mosl  deeply  seated  of  all  the  muscles  of  the  leg.  and  it  lies  between  the  Flexor 
Longus  hallucis  and  the  flexor  longus  digitorum.  Between  its  two  heads  pass 
the  anterior  tibial  vessels  to  the  front  of  the  leg.  Its  tendon  passes  through  a 
groove  behind  the  internal  malleolus  in  its  own  sheath.  It  then  passes  through 
another  sheath  over  the  internal  lateral  ligament  into  the  foot  and  then  beneath 
the  inferior  calcaneonavicular  ligament  to  its  insertion.  It  sends  fibers  of  in- 
sertion to  all  the  bones  of  the  tarsus  except  the  astragalus,  also  to  second,  third, 
and  fourth  metatarsal  bones. 

(  >rigin.  (  Plate  L.) — Whole  of  posterior  surface  of  interosseous  membrane, 
excepting  lowesl  part;  from  outer  portion  of  posterior  surface  of  shaft  of  tibia, 
between  commencement  of  oblique  line  above  and  junction  of  middle  and  lower 
third  of  shaft  below;  from  upper  two-thirds  of  the  internal  surface  of  fibula; 
some  fibers  a  bo  from  deep  transverse  fascia  and  intermuscular  septa. 

I  nsertion.  (Plate  bill.)  —Tuberosity  of  navicular  and  internal  cuneiform 
bono  and  bases  of  second,  third,  ami  fourth  metatarsal. 

Action.     Extends  tarsus;  turns  sole  inward. 

Nerve  Supply.— Fifth  lumbar  and  first  sacral  through  posterior  tibial. 

Blood  Si  pply.     Posterior  tibial. 

Peroneus   longus.-    Description. — (Plate   LXXIX.) — The   Peroneus   Ion- 


ANATOMY    IN    A    NUTSHELL.  1  ")7 

tins  is  superficial  to  the  Peroneus  brevis.     It  is  situated  at  the  upper  part  and 

outside  of  the  leg.  The  external  popliteal  or  peroneal  nerve  passes  between 
the  fibula  and  this  muscle  near  the  upper  part  of  the  bone  between  the  head  and 
the  shaft.  As  its  tendon  passes  behind  the  external  malleolus  it  lies  behind  the 
tendon  of  the  Peroneus  brevis  in  a  common  groove  which  is  converted  into  a 
canal  by  a  fibrous  band.  These  two  tendons  have  synovial  membranes.  Its 
tendon  passes  across  the  outer  side  of  the  os  calcis,  below  its  peroneal  tubercle, 
then  it  runs  in  a  groove  on  the  under  surface  of  the  cuboid  bone  after  which  it 
crosses  the  sole  of  the  foot  obliquely.  Behind  the  external  malleolus  and  on 
the  outer  side  of  the  cuboid  bone  the  tendon  changes  its  direction,  and  in  these 
places  it  is  thickened.  A  sesamoid  fibro-eartilage  (sometimes  a  bone)  is  in  its 
substance  where  it  crosses  the  cuboid  bone. 

Origin. — (Plate  LI.) — (1)  Head  and  upper  two-thirds  of  outer  surface  of 
fibula;  (2)  deep  surface  of  fascia;  (3)  intermuscular  septa  and  occasionally  by 
few  fibers  from  outer  tuberosity  of  tibia. 

Insertion. — (Plate  LIII.) — Outer  side  of  base  of  metatarsal  of  meat  toe 
and  internal  cuneiform.  Occasionally  send-  dip  to  base  of  second  metatarsal 
bone. 

Action. — Extends  and  everts  foot  and  steadies  leg  upon  foot. 

Nerve  Supply. — Fourth  and  fifth  lumbar  and  first  sacral  through  musculo- 
cutaneous branch  of  the  external  popliteal. 

Blood  Supply. — Peroneal. 

Peroneus  brevis. — Description. — (Plate  LXXIX.) — This  muscle  is  shorter 
and  smaller  than  the  Peroneus  longus  and  lies  behind  it.  Its  tendon  passes 
behind  the  external  malleolus  in  front  of  that  of  the  Peroneus  longus.  On  the 
outer  side  of  the  os  calcis  it  is  separated  from  the  tendon  of  the  Peroneus  longus 
by  the  peroneal  tubercle. 

Origin. — (Plate  L.) — Lower  two-thirds  of  external  surface  of  shaft  of 
fibula,  and  intermuscular  septa. 

Insertion. — (Plate  LIII.) — Tuberosity  at  base  of  metatarsal  of  little  tee 
on  its  outer  side. 

Action. — Extends  foot  and  helps  to  steady  leg  upon  foot. 

\ki;\  e  Supply. — Fourth  and  fifth  lumbar  and  hist  sacral  through  musculo- 
cutaneous branch  of  external  popliteal. 

Blood  Supply.  —  Peroneal. 


LESSON   Xidl. 

Extensor  brevis  digitoruin. — Description.— (Plate  LXXV.)— This  is  a 
broad,  thin  muscle  which  passes  obliquely  across  the  dorsum  of  the  foot  and 
divides  into  four  tendons.  Beneath  this  muscle  lie  the  tarsal  and  metatarsal 
arteries  and  bones  and  the  Dorsal  interossei  muscles.  The  innermost  tendon 
crosses  the  dorsalis  pedis  artery. 

Origin. — (Plate  LI  I.) — (1)  Fore  part  of  upper  and  outer  surface  of  <  s  calcis; 
(2)  external  calcaneo-astragaloid  ligament;  (3)  horizontal  portion  of  anterior 
annular  ligament. 


158  ANATOMY    IN    A    NUTSHELL. 

[nsertion. — (Plato  LIU.) — Innermost  tendon  into  dorsal  surface  of  base 
of  first  phalanx  of  great  toe;  the  other  three  into  outer  sides  of  long  extensor 
tendons  of  second,  third  and  fourth  toes. 

Action.  Extends  phalanges  of  four  inner  toes  acting  only  on  first  phalanx 
of  ilif  great  toe. 

N  i  kve  Supply.— Anterior  tibial. 

Blood  Supply. — Dorsalis  pedis. 

Abductor  hallucis.—  Description. — (Plate  LV.) — This  muscle  is  the  inner 
one  "t'  the  three  muscles  of  the  first  layer  of  the  plantar  surface  of  the  foot.  It 
is  protected  by  the  plantar  fascia.  This  fascia  is  beneath  the  muscle  when  one's 
fool  is  on  the  floor. 

Origin.-  (Plate  LI  11.) — (1)  Inner  tubercle  of  under  surface  of  os  calcis;(2) 
internal  annular  ligament;  (3)  plantar  fascia;  (4)   intermuscular  septum. 

Insertion. — (Plate  LIII.) — Inner  side  of  base  of  first  phalanx  of  greattoe. 

Actiox. — Abducts  great  toe;  flexes  proximal  phalanx. 

Nerve  Supply. — Internal  plantar. 

Blood  Supply. — Internal  plantar. 

Abductor  minimi  digiti. — Description. — (Plate  LV.) — This  muscle  is 
separated  from  the  Flexor  brevis  digitorum  by  a  vertical  septum  of  fascia,  and 
has  along  its  inner  border  the  plantar  vessels  and  nerve.  All  the  muscles  of  the 
first  Layer  of  the  foot  bear  the  same  relation  to  the  plantar  fascia. 

Origin. — (Plate  LIII.) — (1)  Outer  tubercle  of  os  calcis;  (2)  under  surface 
of  os  calcic  in  front  of  both  tubercles;  (3)  fore  part  of  inner  tubercle;  (4)  plantar 
fascia:  (5)  intermsucular  septum. 

Insertion. — (Plate  LIII.) — Its  tendon,  after  gliding  over  a  smooth  facet 
on  the  under  surface  of  the  base  of  the  fifth  metatarsal  bone,  is  inserted,  together 
with  the  short  Plexor  of  the  little  toe, into  the  outer  side  of  base  of  first  phalanx 
of  little  toe. 

Action. — Abducts  little  toe;  flexes  proximal  phalanx. 

Nerve  Supply.  —  External  plantar. 

Blood  Supply. — External  plantar. 

Flexor  brevis  digitorum. — (Perforatus.) — Description. — (Plate  LV.) — This 
muscle  is  called  Perforatus  because  its  tendons  are  perforated  by  those  of  the 
Flexor  longus  digitorum  (Perforans.)  After  the  muscle  divides  into  four 
tendons,  one  for  cadi  of  the  four  outer  toes,  these  tendons  themselves  divide 
opposite  bases  of  the  first  phalanges  for  the  passage  of  the  tendons  of  the  Flexor 
longus  digitorum.  They  divide  a  second  time  to  be  inserted  into  the  sides  of 
the  second  phalanx  of  the  four  outer  toes.  This  muscle  is  separated  from  the 
externa]  plantar  vessels  and  nerve  by  a  thin  layer  of  fascia. 

ORIGIN.  (Plate  bill.)— (1)  Inner  tubercle  of  os  calcis;  (2)  central  part 
of  plant  a i-  fascia;  (3)  intermuscular  septa. 

Insertion.-  (Plate  LIII.)     Sides  of  second  phalanges  of  four  lesser  toes. 

\ii  [on.     Flexes  toes. 

\i:i;\  i:  Supply.      Internal  plantar. 

P>!.(»oi>  SUPPLY.-   Plantar  arteries. 

Adductor    obliquus    hallucis.-    Description. — (Plate    LX.) — This    muscle 


PLATE  LIV 


PHALANGES.  TWO  CENTERS  FOR  EACH 
BONE.  ONE  FOR  SHAFT.  ONE  FOR  METATARSAL  EXTREM  ITY 

THE  CENTERS  FOR  THE  BASE  OF  THE  TERMINAL  PHA- 
LANGES APPEAR  AT  THE  SIXTH  YEAR.  CONSOLIDATE  AT 
THE  EIGHTEENTH  YEAR. 


THE  CENTERS  FOR  THE  HEADS 
OF  THE  METATARSALS  APPEAR 
AT  THE  THIRD  YEAR,  AND 
CONSOLIDATE  AT  THE 
TWENTIETH  YEAR. 


METATARSUS 

TWO  CENTERS  FOR  EACH  BONE. 
ONE  FOR  SHAFT  ONE  FOR  DIGITAL 
EXTREMITY    EXCEPT  FIRST 

THE  CENTER  hOR  THE  EPIPHYSIS 
FOR  THE  METATARSAL  OF  THE  HALLUX 
APPEARS  AT  THE  THIRD  YEAR. 
CONSOLIDATES  AT  THE  TWENTIETH  YEAR. 


ONE  CENTER  FOR  EACH  BONE.  EXCEPT  OS  CALCIS 


THE  CENTER  FOR  THE  EPIPHYSIS  FOR  THE  CAL- 
CANEUM  APPEARS  AT  THE  TENTH  YEAR.  CONSOLIDATES 
AT  SIXTEENTH  YEAR. 


Showing  the  Direction  op  Nutrient  Arteries  of  Bones  of  the  Foot. 

159 


160  ANATOMY    IN    A    NUTSHELL 

occupies  the  hollow  space  between  the  four  inner  metatarsal  bones.     It  is  a 
large,  thick,  fleshy  mass  passing  obliquely  across  the  foot. 

Origin. — (Plate  LIII.) — Tarsal  extremities  of  second,  third,  and  fourth 
metatarsals  and  sheath  of  tendon  of  Peroneus  longus. 

Insertion. — (  Plate  LIII.) — Outer  side  of  base  of  first  phalanx  of  great  toe, 
with  outer  portion  of  Flexor  brevis  hallucis.  All  the  small  muscles  of  the  great 
toe  give  off  fibrous  expansions  at  their  insertion  to  blend  with  the  long  extensor 
tendon. 

Action. — Abducts  great  toe. 

Nerve  Supply. — External  plantar. 

Blood  Supply.  —  Plantar  arteries. 

Adductor  transversus  hallucis. — Description.  —  (Plate  LX.) — This  muscle 
is  narrow  ami  fiat,  and  crosses  the  heads  of  metatarsal  bones,  lying  between 
them  and  the  flexor  tendons.  Another  name  for  this  muscle  is  (Transversus 
pe<  lis.) 

Origin. — (Plate  LIII.) — Inferior  metatarso-phalangeal  ligaments  of  three 
outer  toes. 

Insertion. — (Plate  LIII.) — Outer  side  of  first  phalanx  of  great  toe,  its 
fibers  being  blended  with  the  tendon  of  insertion  of  the  Adductor  obhquus 
hallucis. 

A<  tion. — Adducts  great  toe. 

Xi;i;\  e  Sipply. — External  plantar. 

Blood  Supply. — External  plantar. 

Dorsal  interossei. — Description. — (Plate  LXI.) — The  Dorsal  interossei 
of  the  foot  are  similar  to  those  in  the  hand  with  the  exception  that  they  are 
grouped  around  the  middle  line  of  the  second  toe,  while  those  of  the  hand  are 
grouped  around  the  middle  line  of  the  middle  finger.  Each  one  lias  two  heads 
between  which  pass  the  perforating  arteries  to  the  dorsum  of  the  foot,  except  in 
the  hirst  dorsal  interosseous  between  the  two  heads  of  which  passes  the  com- 
municating branch  of  the  dorsalis  pedis  artery. 

ORIGIN.      (Plate   LXI.) — From  adjacent  sides  of  metatarsal  bones. 

Insertion. — (Plate  LXI.) — Bases  of  first  phalanges  and  aponeurosis  of 
common  extensor  tendon;  first  muscle  inserted  into  inner  side  of  second  toe, 
the  other  three  into  outer  side  of  second,  third,  and  fourth  toes. 

Action.— Flex  first  and  extend  second  and  third  phalanges ;  adduct  second, 
third,  ami  fourth  tin-. 

Nerve  Supply.  External  plantar.  First  and  second  dorsal  also  receive 
extra  filaments  from  anterior  tibial  nerve. 

Blood  Supply.  The  Plantar  interossei  receive  the  external  plantar,  and 
the  Dorsal  interossei  receive  the  plantar  arteries  both  external  and  internal;  ex- 
cept the  third  dorsal  interosseous  which  receives  the  external  only. 

Plantar  interossei.  DESCRIPTION.— (Plate  LXII.) — The  plantar  inter- 
""i  i  ;ire  three  in  number,  the  same  as  the  palmar  interossei  of  the  hand  and  also 
have  one  head  apiece.      They  lie  beneath  the  metatarsal  bones. 

ORIGIN.— (Plate  LXII.)  Base  ami  inner  side  of  shaft  of  third,  fourth. 
and  fifth  metatarsal  bones. 


ANATOMY    IN    A    NUTSHELL. 


161 


Insertion. — (Plate  LXII.) — Inner  sides  of  bases  of  first  phalanges  of  same 
toes  and  aponeurosis  of  common  extensor  tendon. 

Action. — Adduct  first  phalanges  of  three  outer  toes;  also  flex  first  phalanges, 
but  extend  the  rest. 

Nerve  Supply. — External  plantar. 

Blood  Supply. — Plantar  arteries. 

PLATE  LV. 


EXTERNAL 
NERVE  .PLANTAR 


Plantar  Fascia  and  First  Layer  of  Muscles  of  Foot. 


LESSON  XLII1. 

Flexor  accessorius. —  Description.  (Plate  LIX.)  The  two  heads  of  this 
muscle  are  separated  from  each  other  by  the  Long  plantar  Ligament.  The  ex- 
ternal plantar  vessels  and  nerve  lie  beneath  it .  when  one  is  standing. 


162  ANATOMY    IN    A    NUTSHELL. 

Origin. — (Plate  L1II.) — Inner  or  larger  head  from  inner  concave  surface 
of  os  calcis  below  groove  for  tendon  of  Flexor  longus  hallucis.  Outer  head  from 
outer  surface  of  OS  calcis  and  long  plantar  ligament. 

[nsertion.  (Plate  LIX.) — Outer  margin,  upper  and  under  surfaces  of 
tendon  of  Flexor  Longus  digitorum. 

A<  pion.     Assists  long  flexors  of  toes. 

Nerve  Supply. — External  plantar. 

Bl Si  ppli  .      External  plantar. 

Lumbricales.—  Description. — (Plate  LIX.) — These  are  accessory  to  ten- 
dons of  the  Flexor  Longus  digitorum. 

Origin.  -(Plate  LIX.) — Tendons  of  long  flexors. 

Insertion. — (Plate  LIX.) — Expansion  of  long  extensors  and  base  of  first 
phalanx  of  corresponding  toe. 

A<  riON.     Accessory  to  flexors  and  extensors. 

\i  i;\  i.  Supply. — Two  inner  muscles  get  the  internal  plantar.  Two  outer 
muscles  gel    the  external  plantar. 

Note. — The  first  inner  lumbricalis  has  internal  plantar  and  the  three  outer 
have  external  plantar  in  one  out  of  ten  cases. 

Blood  Supply. — Plantar  arteries. 

Flexor  brevis  hallucis. — Description. — (Plate  LX.) — This  muscle  has  one 
origin  and  two  insertions,  and  is  situated  along  the  inner  and  under  surfaces  of 
the  metatarsal  of  the  great  toe.  The  inner  tendon  joins  that  of  the  Abductor 
lialluci-.  while  the  outer  one  joins  the  tendons  of  the  Adductor  transversus 
hallucis  and  the  Adductor  obliquus  hallucis  prior  to  their  common  insertion  in  a 
sesamoid  bone.  Between  these  two  heads  the  Flexor  longus  hallucis  lies  in  a 
ive. 

Origin. — (Plate  LIII.) — (1)  Inner  border  of  cuboid  bone;  (2)  external 
cuneiform;  (3)  prolongation  of  tendon  of  Tibialis  posticus. 

Insertion.  (Plate  LIII.) — Inner  and  outer  sides  of  base  of  first  phalanx 
of  greal  toe. 

Action.  —Flexes  and  abducts  great  toe. 

N i:i;\  i.  Supply.     Internal  plantar. 

Blood  Supply.—  Internal  plantar. 

Astragalus,  supplied  by  dorsalis  pedis.     One  or  two  centers  of  ossification. 

Artici  LATION.  With  four  bones:  (1)  tibia,  (2)  fibula;  (3)  os  calcis,  and 
navicular. 

Astragalus  has  no  muscles  attached. 

Os  calcis,  supplied  by  posterior  tibial,  internal  and  external  malleolar.  Two 
centers  of  ossifk  moN.     For  ossification  of  tarsus  see  Plate  LIY. 

Artk  i  LATION.      With  two  bones:   (1)   the  astragalus  and  (2)   cuboid. 

Attachment  oi  Muscles.  Eight:  (1)  part  of  the  Tibialis  posticus;  (2) 
the  tendon  Achillis;  (3)  Plantaris;  (4)  Abductor  hallucis;  (5)  Abductor  minimi 
digiti;  (6)  Flexor  brevis  digitorum;  (7)  Plexor  accessorius,  and  (8)  Extensor 
brevis  digitorum. 

Cuboid,  supplied  by  the  dorsalis  pedis, as  are  the  remaining  bones  of  tarsus. 

( >ssn  [(  vi  [on.     (  me  center. 


ANATOMY    IN    A    NUTSHELL. 


163 


Articulation. — With  four  bones;  (1)  the  os  calcis;  (2)  external  cunei- 
form, and  (3)  the  fourth  and  (4)  fifth  metatarsal  bones;  occasionally  with  the 
navicular. 

Attachment  of  Muscles.— (1)  part  of  the  Flexor  brevis  hallucis  and  (2) 

PLATE  LVI. 


First  Layer  of  Muscles  of  the  Foot,  Also  [nternal   wi>  External 

Plantar  Arteri  es. 

a  slip  from  the  tendon  of  the  Tibialis  posticus. 

Navicular,  supplied  by  dorsalis  pedis. 

(  Ossification. — One  center. 

Articulation.— With   four   hones:  (1)  astragalus   and    three   cuneiform; 
occasionally  the  cuboid. 

Attachment  of  Muscles.     Pari  of  the  Tibialis  posticus. 

Internal  cuneiform,  supplied  by  dorsalis  pedis. 


164  ANATOMY    IN    A    NUTSHELL. 

Ossification. — One  center. 

Articulation. — With  four  bones:  (1)  navicular,  (2)  middle  cuneiform; 
(3)  first  and  (4)  second  metatarsal  bones. 

Attachment  of  Muscles. — (1)  Tibialis  anticus  and  (2)  posticus  and  (3) 
Peroneus  longus. 

Middle  cuneiform,  supplied  by  dorsalis  pedis. 

i  >ssification. — One  center. 

Ai;ii<  qlation. — With  four  bones,  navicular,  internal  and  external  cunei- 
form and  second  metatarsal  bone. 

Attachment  of  Muscles. — A  slip  from  the  tendon  of  the  Tibialis  posticus 
is  attached  to  this  bone. 

External  cuneiform,  supplied  by  dorsalis  pedis. 

Ossification. — One  center. 

Articulation. — With  six  bones;  the  navicular,  middle  cuneiform,  cuboid, 
second,  third,  and  fourth  metatarsal  bones. 

Attachment  of  Muscles. — Two:  part  of  Tibialis  posticus,  Flexor  brevis 
hallucis. 

Metatarsus.     Plates  LII-LIII. 

Blood  Supply. — They  all  have  small  nutrient  branches  from  interosseous. 

Ossification. — Each  metatarsal  bone  has  two  centers.     Plate  LIV. 

Articulation. — Each  bone  articulates  with  the  tarsal  bones  by  one  ex- 
tremity, and  by  the  other  with  the  first  row  of  phalanges.  The  number  of  tarsal 
bones  with  which  each  metatarsal  articulates  is  one  for  the  first,  three  for  the 
second,  one  for  the  third,  two  for  the  fourth,  and  one  for  the  fifth. 

Attachment  of  Muscles. — To  the  first  metatarsal  bone,  three,  part  of  the 
Tibialis  anticus,  the  Peroneus  longus,  and  First  dorsal  interosseous.  To  the 
second,  four,  the  Adductor  obliquus  hallucis  and  First  and  Second  dorsal  inter- 
osseous, and  silp  from  the  tendon  of  the  Tibialis  posticus,  and  occasionally  a 
slip  from  the  Peroneus  longus.  To  the  third,  five,  the  Adductor  obliquus  hallucis, 
Second  and  Third  dorsal  and  Plrst  plantar  interosseous,  and  a  slip  from  the 
tendon  of  the  Tibialis  posticus.  To  the  fourth,  five,  the  Adductor  obliquus 
hallucis.  Third  and  fourth  dorsal,  and  Second  plantar  interosseous,  and  a  slip 
from  the  tendon  of  the  Tibialis  posticus.  To  the  fifth,  six,  the  Peroneus  brevis 
Peroneus  tertius,  Flexor  brevis  minimi  digiti,  Adductor  transversus  hallucis. 
Fourth  dorsal  and  Third  plantar  interosseous. 

Phalanges.     Plates   LII-LIII. 

Blood  Supply. — They  all  have  small  nutrient  branches  from  digital. 

Ossification.-   From  two  centers.     Plate  LIV. 

Artk  i  LATION.  The  first  row,  with  the  metatarsal  bones  behind  and  sec- 
ond phalanges  in  front  ;the  second  row  of  the  four  outer  toes,  with  the  first  and 
third  phalanges;  of  the  great  toe,  with  the  first  phalanx:  the  third  row  of  the 
loin-  outer  toes,  with   the  second  phalanges. 

Attachment  ok  Muscles.-  To  the  first  phalanges.  Great  toe,  five  mus- 
cles; innermosl  tendon  of  Extensor  brevis  digitorum,  Abductor  hallucis,  Ad- 
ductor obliquus  hallucis,  flexor  brevis  hallucis,  Adductor  transversus  hallucis. 


ANATOMY    IN    A    NUTSHELL. 


165 


Second  toe,  three  muscles ;  First  and  Second  dorsal  interosseous  and  First 
lumbrical.  Third  toe,  three  muscles ; Third  dorsal  and  First  plantar  interosseous 
and  Second  lumbrical.  Fourth  toe,  three  muscles;  Fourth  dorsal  and  Second 
plantar  interosseous  and  Third  lumbrical.  Fifth  toe,  four  muscles;  Flexor  brevis 
minimi  digiti.  Abductor  minimi  digiti,  and  Third  plantar  interosseous,  and 

PLATE  LVII. 


INTERNAL    PLANTAR 


LUMBRICALES 


ARTERY 
INTERNAL    PLANTAR 
NERVE. 


ARTERY. 

POST.  TIBIAL 

NERVE 


EXTERNAL    PLANTAR 


COMMUNICATING 
TO  INTERNAL  PLANTAR 


NERVE 

EXTERNAL  PLANTAR 

ARTERY 


LUMBRICALES,   INTERNAL    AND    EXTERNAL   PLANTAH     VESSELS    AND    NERVES. 

Fourth  lumbrical.  Second  phalanges.  Great  toe;  Extensor  Longus  hallucis, 
Flexor  longus  hallucis.  Other  toes;  Flexor  brevis  digitorum;  one  slip  ol  the 
common  tendon  of  the  Extensor  longus  and  brevis  digitorum.     Third  phalanges; 

two  slips  from  the  common  tendon  of  the  Extensor  longus  and  Extensor  brevis 
digitorum,  and  the  Flexor  longus  digitorum. 


166  ANATOMY    IN    A    NUTSHELL. 

LESSON  XL1Y. 

The  Tibia. 

The  word  tibia  means  flute.  It  is  also  called  the  shin  bone  and  is  situated 
on  a  plane  anterior  to  and  on  the  inner  side  of  the  fibula.  It  articulates  with  the 
lemur  above,  tin1  astragalus  below,  and  the  fibula  externally.  It  sustains  the 
uri'Jn  of  the  entire  body  above  the  knee-joint  as  the  fibula  does  not  enter  into 
this  articulation. 

The  superior  expanded  portion  is  called  the  head,  each  side  of  which  is  a 
tuberosity.  These  tuberosities  are  continuous  in  front  but  are  separated  be- 
hind by  the  popliteal  notch.  The  upper  surface  of  each  tuberosity  is  concave 
to  receive  the  condyles  of  the  femur. 

The  internal  tuberosity  is  larger  than  the  external  one,  and  its  articular 
surface  is  more  concave  and  Longer.  A  horizontal  groove  for  the  Semimem- 
branosus muscle  is  behind  this  articular  surface  close  to  its  inner  border. 

The  external  tuberosity  gives  attachment  to  the  ilio-tibial  band  at  the  junc- 
tion of  the  anterior  and  outer  surfaces,  at  which  place  there  is  a  prominent  tuber- 
cle. The  Extensor  Longus  digitorum  and  the  Biceps  have  a  \'v\\  fibers  of  at- 
tachment immediately  below  and  in  front.  The  fibula  articulates  with  the 
posterior  and  under  part  in  a  flat  facet  which  looks  downward,  outward,  and 
backward.  The  articular  surface  of  this  tuberosity  is  concave  from  side  to  side, 
but  convex  from  before  backward,  and  its  circumference  is  almost  circular. 
The  semilunar  fibro-cartilages  are  situated  around  the  circumference  of  each 
of  these  articular  surfaces  where  they  are  flattened. 

The  spine  is  an  elevation  between  these  articular  surfaces.  The  summit  of 
the  spine  has  two  tubercles  with  an  intervening  space.  The  depressions  in 
iVi .lit  and  behind  the  spine  are  for  the  attachment  of  the  crucial  ligaments. 
This  posterior  depression  is  continuous  into  the  popliteal  notch,  which  separates 
the  tuberosities  posteriorly.  The  anterior  tuberosity  or  tubercle  is  at  the  junc- 
tion of  the  head  and  the  -haft  anteriorly.  The  lower  half  of  this  tubercle  gives 
attachment   to  the  ligamentum  patellae. 

The  shaft  which  is  triangular  on  cross  section  is  smallest  at  the  junction  of 
the  upper  two-thirds  with  the  lower  one-third.  It  has  three  borders  and  three 
surfaces.  The  anterior  border  separates  the  internal  and  external  surfaces  and 
extends  from  the  anterior  tuberosity  or  tubercle  to  the  front  of  the  inner  mal- 
leolus.  The  crest  of  the  tibia  i>  the  upper  two-thirds  of  this  border.  The  lower 
one-third  of  this  border  is  smooth.  The  internal  border  separates  the  internal 
and  posterior  surfaces.  It  commences  above  at  the  back  of  the  inner  tuberosity 
and  extends  below  to  the  posterior  border  of  the  internal  malleolus.  This 
border  ie  rnos1  distind  in  the  middle  third  of  the  bone.  The  external  border, 
also  called  interosseous  ridge,  separate-  the  external  and  posterior  surfaces.  It 
gives  attachment  to  the  interosseous  membrane  and  is  thin  and  sharp  in  its 
middle  portion. 

The  internal  surface  is  nearly  subcutaneous  and  is  convex.     The  insertion 


ANATOMY    IN    A     NUTSHELL. 


167 


of  the  Gracilis  is  at  the  inner  side  of  the  tubercle,  having  the  insertion  of  the 
Semitendinosus  below  it.  the  two  being  surrounded  by  the  double  insertion  of 
the  Sartorius.  except  below.  The  external  surface  has  on  it-  upper  two-thirds, 
which  is  concave,  the  Tibialis  anticus.  The  lower  part  of  its  surface  runs  for- 
ward and  is  covered  by  the  extensor  tendons.     The  posterior  surface  has  an 

PLATE  LVIII. 


Accessorius  Muscle  and  Plantar  Vessels. 

oblique  line  running  down  and  inward  a1  the  junction  of  the  upper  and  middle 
one-third  of  the  bone.  This  line  giv<  -  the  origin  of  the  Soleus.  The  popliteus 
muscle  is  attached  to  the  triangular  area  above  this  line.  The  middle  one- 
third  of  the  bone  is  divided  into  two  portion-  by  a  longitudinal  ridge,  the  inner 
one  of  which  is  for  the  origin  of  the  Flexor  longus  digitorum,  and  the  outer  one 


168  ANATOMY    IN   A    NUTSHELL. 

is  for  the  origin  of  the  Tibialis  posticus.  A  nutrient  foramen  is  on  this  portion 
of  the  bone  and  is  directed  towards  the  distal  extremity. 

The  lower  portion  of  the  bone  is  broad  transversely,  and  extends  downward 
internally  to  form  the  inner  malleolus.  On  the  posterior  portion  of  this  malleo- 
lus is  a  groove  for  the  tendon  of  the  Tibialis  posticus,  and  externally  to  this  is 
one  for  the  tendon  of  the  Flexor  longus  hallucis.  The  fibula  articulates  with  the 
external  portion  of  the  lower  extremity  of  the  bone  in  a  concave  surface,  which 
is  rough  for  the  attachment  of  ligaments,  except  along  its  lower  border.  The 
lower  end  of  the  tibia  has  an  articular  surface  which  is  concave,  being  broader 
in  front  than  behind.  It  articulates  with  the  astragalus.  In  the  middle  of 
thi>  surface  is  a  slight  elevation  separating  two  lateral  depression-. 

The  tibia  is  a  very  vascular  bone.  The  nutrient  artery  for  the  shaft  is 
furnished  by  the  posterior  tibial,  it  enters  the  bone  near  the  interosseous  border 
at  the  junction  of  the  upper  and  middle  third,  and  is  directed  downward.  The 
head  of  the  bone  receives  numerous  branches  from  the  inferior  articular  arteries 
of  the  popliteal,  and  the  recurrent  branches  of  the  anterior  and  posterior  tibial 
arteries.  The  lower  extremity  receives  twigs  from  the  posterior  and  anterior 
tibial,  the  anterior  peroneal,  and  the  internal  malleolar  arteries. 

Ossificatiox. — From  three  centers.  The  center  for  the  shaft  appears  in 
the  eighth  week  of  intra-uterine  life.  The  center  for  the  proximal  extremity 
appears  at  the  end  of  the  ninth  month  of  intra-uterine  life,  and  joins  the  shaft 
at  the  twenty-first  year  or  even  later.  The  center  for  the  distal  extremity  ap- 
pears during  the  second  year  and  unites  with  the  shaft  at  the  eighteenth  year. 

Articulation. — With  three  bones;  femur,  fibula  and  astragalus. 

Attachment  of  Muscles. — Twelve;  to  the  inner  tuberosity,  the  Semi- 
membranosus; to  the  outer  tuberosity,  the  Tibialis  anticus  and  Extensor  longus 
digitorum  and  Biceps;  to  the  shaft,  its  internal  surface,  the  Sartorius,  Gracilis, 
and  Semitendinosus;  to  its  external  surface,  the  Tibialis  anticus;  to  its  posterior 
surface,  the  Popliteus,  Soleus,  Flexor  longus  digitorum,  and  Tibialis  posticus; 
to  the  tubercle,  the  hgamentum  patellae. 


LESSON  XLY. 
The  Patella. 

The  sesamoid  bone  which  is  developed  in  the  tendon  of  the  Quadriceps 
extensor  muscle  is  the  patella  (knee-pan.)  Its  anterior  surface  is  pierced  by 
vascular  foramina.  h>  superior  border  has  the  Rectus  and  Crureus  attached 
to  it.     The  posterior  margin  of  this  border  is  higher  than  the  anterior  margin. 

The  externa]  part  of  the  posterior  surface  is  concave  transversely,  and  the 
interna]  pari  i-  convex.  When  the  leg  is  extended  the  lower  one-sixth  of 
articular  surface  is  in  contact  withthe  femur.  When  it  is  mid-flexed  the  middle 
three-sixths  of  the  articular  surface  is  in  contact  with  the  femur.  When  fully 
flexed  the  upper  two-sixths  of  the  articular  surface  is  in  contact  with  the  femur, 
also  in  this  position  the  marginal  facet  is  in  contact  with  the  inner  condyle. 
The  Ugamentum  patellae  springs  from  the  apex.     If  the  patella  is  placed  upon  a 


ANATOMY  IN  A   NUTSHELL. 


169 


plain  surface,  its  apex  away  from  you  and  its  anterior  surface  up,  it  will  tip  to 
the  side  to  which  it  belong?. 

Blood  Supply.— The  patella  receives  twigs  from  the  superficial  branch 
of  the  anastomotica,  anterior  tibial  recurrent,  and  the  inferior  articular  of  the 
popliteal. 


'ft 

j      |t       /      •'  LUMBRICALIS_  V    /   | 

1  iff 


Flexor  Lonqtjs  Digitorum  Tendon  and  Foub   Lumbricales. 

Ossification. — One  center.  It  begins  during  the  third  year  and  is  com- 
pleted aboul  the  age  of  puberty. 

Articulation.— With  two  condyles  of  femur. 

Attachment  of  Muscles.— Four :  the  Rectus,  Crureus,  Vastus  interims 
and  Vastus  externus.  These  muscles,  joined  at  their  insertion,  constitute  the 
Quadriceps  extensor  cruris. 


170  anatomy  in  a  nutshell. 

The  Fibula. 

The  word  fibula  means  clasp  or  pin.  It  is  also  called  the  peroneal  bone, 
and  Lies  almost  parallel  with  the  tibia.  It  is  not  quite  as  long  as  the  tibia,  but 
extends  to  a  Lower  Level.     Its  main  purpose  is  to  give  elasticity  to  the  leg. 

1 1-  upper  expanded  portion  is  called  the  head,  which  is  prolonged  upward 
at  its  posterior  part  into  the  styloid  process.  The  inner  surface  of  the  head 
and  styloid  process  has  a  facet  which  looks  upward,  inward,  and  forward  to 
articulate  with  the  tibia.  This  styloid  processgives  attachment  to  the  Biceps. 
The  Soleus  muscle  is  attached  behind  and  the  Peroneus  longus  is  attached  in 
front.  The  neck  is  the  constricted  part  below  the  head.  The  lower  extremity 
extends  into  the  external  malleolus  which  is  lower  than  the  internal  malleolus. 
.Man  i-  the  only  animal  in  which  this  is  true.  It  articulates  with  the  astragalus 
internally,  and  behind  there  is  a  depression  for  the  posterior  fasciculus  of  the 
external  lateral  ligament.  There  is  a  slight  groove  posteriorly  for  the  Peroneus 
longus  and  brevis.     This  extremity  is  convex  and  subcutaneous  externally. 

The  shaft  has  four  surfaces  which  are  anterior,  internal,  posterior,  and 
external;  and  it  has  four  borders  which  are  antero-external,  antero-in- 
ternal,  postero-external,  and  postero-internal.  To  its  anterior  surface 
are  attached  the  Extensor  proprius  hallucis,  Extensor  longus  digitorum,  and 
Peroneus  tertius.  This  surface  is  broad  and  grooved  below  but  narrow  above. 
The  internal  surface  is  grooved  for  the  Tibialis  posticus.  The  posterior  surface 
has  attached  to  its  upper  third  the  Soleus,  below  this  the  Flexor  longus  hallucis. 
The  nutrient  canal  is  on  this  surface  and  is  directed  downward.  The  Peroneus 
brevis  and  longus  are  attached  to  the  external  surface,  which  is  directed  out- 
ward  above   and   backward   below. 

The  antero-external  border  is  between  the  peroneal  muscles  and  the  ex- 
tensor  muscles,  and  extends  from  the  front  of  the  head  of  the  fibula  to  the  ex- 
ternal malleolus,  where  it  divides  to  embrace  a  triangular  subcutaneous  sur- 
face. The  antero-internal  border,  called  interosseous  ridge,  gives  attachment  to 
the  interosseous  membrane  and  separates  the  extensor  muscles  in  front  from 
the  Tibialis  posticus  behind.  It  lies  parallel  with  the  antero-external  border 
in  it-  upper  third.  It  ends  below  just  above  the  articular  facet.  The  pos- 
tero-external border  separate-  the  peroneal  muscles  from  theflexor  muscles.  It 
commences  a1  the  base  of  the  styloid  process  and  ends  below  in  the  posterior 
border  of  the  external  malleolus.  This  is  not  a  straight  line  for  at  first  it  is 
directed  outward,  then  backward,  then  inward.  The  postero-internal  border, 
called  the  oblique  line,  commences  above  the  inner  side  of  the  heads  and  ends 
below  in  the  lower  one-fourth  of  the  bone  where  it  joins  the  interosseous  ridge, 
or  antero-internal  border. 

lb >  Supply.     The  fibula  receives  the  nutrient  artery  of  its  shaft  from 

the  peroneal  branch  of  the  posterior  tibial.  The  head  is  nourished  by  branches 
from  the  inferior  external  articular  branch  of  the  popliteal  artery,  and  the 
malleolus  i-  supplied   mainly  by  the  peroneal  and  external  malleolar   arteries. 

Ossification.  From  three  centers.  The  center  for  the  shaft  appears 
in  the  eighth  week  of  intra-uterine  life.     The  center  for  the  proximal  extremity 


AXATOMY    IN    A    NUTSHELL. 


171 


appears  in  the  fourth  or  fifth  year,  and  joins  the  shaft  at  the  twenty-second 
year  or  later.  The  center  for  the  distal  extremity  appears  during  the  second 
year,  and  unites  with  the  shaft  at  the  twentieth  year. 

Articulation-.— With  two  bones:  the  tibia  and  the  astragalus. 

Attachment  of  Muscles.— Nine ;  to  the  head,  the  Biceps.  Sol.-us.  and 

PLATE  LX. 


FLEXOR  LONGUS  HALLUCIS 
SESAMOID  BONE: 


-  . 

&    ec     •      £j  fV  t?   >N         i       i,       /     ' 


FLEXOR  BREVIS  HALLUCIS 


-      ■        ?-  \ 


TIBIALIS  POSTICUS 


FLEXOR  LONGUS  DIGITORUM  - 


FLEXOR  LONGUS  HALLUCIS 


. 


GROOVE  FOR  PERONEUS  LONGUS 


Third  Later  of  Must  les  of  the  Foot. 


Peroneus  Iongus;  to  the  shaft,  its  anterior  surface,  the  Extensor  longus  digi- 
torum,  Peroneus  tertius,  and  Extensor  proprius  hallucis;  to  the  internal  surface, 
the  Tibialis  posticus;  to  the  posterior  surface,  the  Soleus  and  Flexor  longus  hal- 
lucis: to  the  external  surface,  the  Peroneus  longus  and  brevis. 

The  fibula  is  a  vestigial  bone  in  man  and  survives  mainly  on  account  of 
the  excessive  development  of  its  malleolus.     This  accounts  for  the  fad  thai  the 


172  ANATOMY    IN    A    NUTSHELL. 

lower  epiphysis,  through  appearing  first,  unites  with  the  shaft  before  the  upper 
epiphysis.  In  birds,  the  head  of  the  bone  is  large,  and  enters  into  the  formation 
of  the  knee-joint,  while  the  lower  end  atrophies.  The  rule  is  this:  Those  ephy- 
ses  which  are  the  last  to  form  are  first  to  join  the  bone.  The  fibula  is  an  excep- 
tion.   Rule  1,  page  19. 


LESSOX  XLVI. 

Arteries 

The  abdominal  aorta  (Plates  LXXII-XC)  divides  into  the  right  and  left 
common  iliac  arteries  a  little  to  the  left  side  of  the  median  line  of  the  fourth 
lumbar  vertebra.  This  division  is  on  a  level  with  the  highest  points  of  the  crest 
of  the  ilii.  Each  of  these  common  iliac  arteries  divides  into  an  external  and  an 
internal  iliac  branch  at  the  lumbo-sacral  joint.  The  branches  of  these  com- 
mon iliac  arteries  supply  the  peritoneum,  ureter.  Psoas  magnus. 

The  internal  iliac  branch  (Plates  LXXII-XCI)  is  about  an  inch  and  a  half 
long  and  divides  into  an  anterior  and  posterior  trunk  at  the  upper  margin  of 
the  great  sacro-sciatic  foramen.  The  posterior  trunk  gives  off  the  three  fol- 
lowing branches:  (1)  Ilio-hmibar,  (2)  lateral  sacral,  (3)  gluteal.  The  ilio- 
lumbar branch  divides  into  an  iliac  branch  for  the  Iliacus  muscle  and  the  ilium 
and  a  lumbar  branch  for  the  Psoas  magnus  and  Quadratus  lumborum.  The 
branch  to  the  Quadratus  lumborum  semis  a  spinal  branch  to  the  spinal  cord 
through  the  last  intervertebral  foramen.  The  lateral  sacral  branch  divides 
into  a  superior  and  inferior  division.  The  superior  one,  after  anastomosing 
with  the  sacro-media,  passes  through  the  first  or  second  anterior  sacral  foramen 
to  supply  the  canal,  after  which  it  passes  through  the  corresponding  posterior 
foramen  to  the  back.  The  inferior  branch,  after  descending  on  the  sacrum  and 
coccyx,  anastomoses  with  the  sacro-media  and  has  a  similar  route  as  the  super- 
ior branch. 

The  gluteal  branch  passes  out  of  the  pelvis  through  the  great  sacro-sciatic 
foramen,  above  the  Pyriformis  muscle.  While  in  the  pelvis,  it  gives  branches 
to  the  ilium  and  adjacent  muscles.  Outside  of  the  pelvis  it  divides  into  super- 
ficial branch  which  passes  undes  the  Gluteus  maximus,  and  deep  branch  which 
passes  between  the  Gluteus  medius  and  Gluteus  minimus,  and  then  divides  into 
an  upper  branch  which  runs  along  the  upper  border  of  the  Gluteus  minimus, 
and  a  lower  branch  which  runs  downward. 

The  anterior  trunk  (Plate-  LXXII-XC)  uives  off  the  following  branches: 
(!)  Superior  vesical,  (2)  middle  vesical,  (3)  inferior  vesical.  (4)  middle  hem- 
orrhoidal. (.">)  obturator.  (Co  internal  pudic,  (7)  sciatic;  and  in  the  female  (8) 
uterine,  ami  (9)  vaginal.  The  superior  vesical  branch  is  that  portion  of  the 
fetal  hypogastric  artery  which  is  still  used  alter  birth.  It  runs  to  the  side  of 
the  bladder  and  gives  off  the  artery  to  the  vas  deferens,  which  artery  runs  with 
tin-  spermatic  cord.  In  the  fetus  the  external  iliac  artery  is  only  about  one- 
half  as  large  a-  this  hypogastric  artery  (umbilical).  This  artery  in  the  fetus 
runs  to  the  bladder  and  from  there  along  the  abominal  wall  to  pass  through  the 


ANATOMY    IN    A    NUTSHELL 


173 


umbilicus  to  the  umbilical  cord  and  the  placenta,  (Plate  IX).  The  middle 
vesical  branch  passes  to  the  base  of  the  bladder  and  is  generally  a  branch  of  the 
superior  vesical.  The  inferior  vesical  branch  runs  to  the  base  of  the  bladder, 
prostate  gland  and  seminal  vesicales  in  the  male  and  to  the  vagina,  rectum,  and 
neck  of  the  bladder  in  the  female.  In  the  female  it  is  called  vaginal.  The 
middle  hemorrhoidal  branch  passes  to  the  rectum  and  generally  arises  with  the 

PLATE  LXI. 


The  Four  Dorsal  Interossei. 
inferior  vesical.  The  obturator  branch  lies  inferior  to  the  obturator  nerve,  and 
after  passing  through  the  obturator  canal  it  divide  s  into  an  internal  and  an  ex- 
ternal branch,  which  branches  wind  around  either  margin  of  the  obturator 
foramen  under  the  Obturator  externns  muscle.  This  branch  arises  from  the 
d(  ep  epigastric  once  in  three  and  a  half  cases,  and  pass*  >  over  the  outer  margin 
of  the  femoral  ring  to  the  obturator  foramen.  Inside  the  pelvis  it  sends  branches 
to  the  Iliacus  muscle  and  iliac  fossa,  branches  to  the  bladder,  and  pubic  branches 
to  the  back  of  the  OS  pubis.  The  internal  puttie  branch  is  the  -mailer  of  the 
terminal  branches  of  the  anterior  trunk,  and  passes  ou1  of  the  pelvis  below  the 


174  ANATOMY    IN    A    NUTSHELL. 

Pyriformis  muscle,  lying  between  this  muscle  and  the  Cuccygeus.  After  cross- 
ing the  spine  of  the  ischium,  external  to  the  nerve,  it  passes  through  the  lesser 
sacro-sciatic  foramen  into  the  pelvis,  it  now  passes  through  Aleock's  canal 
about  an  inch  and  a  half  above  the  tuberosity  of  the  ischium,  it  now  pierces  the 
triangular  ligament  where  it  divides  into  the  dorsal  artery  of  the  penis  and  the 
artery  of  the  corpus  cavernosum.  Besides  these  two  terminal  branches  it  has 
the  (1)  muscular,  (2)  inferior  hemorrhoidal.  (3)  superficial  perineal,  (4)  trans- 
perineal,  (5)  artery  of  the  bulb.  The  sciatic  branch  is  the  larger  of  the 
terminal  branches  of  the  anterior  trunk  and  passes  through  the  great  sacro- 
sciatic  foramen  below  the  Pyriformis,  then  descends  between  the  tuberosity  of 
the  ischium  and  the  trochanter  of  the  femur  under  the  Gluteus  maximus,  and 
then  helps  to  form  the  crucial  anastomosis  which  is  made  by  four  branches,  the 
first  three  of  which  are  branches  of  the  profunda  artery  and  the  fourth  is  the 
S<  [atii  BRANCH.  The  first  three  branches  are  named  internal  circumflex, 
external  circumflex,  and  superior  perforating.  Inside  the  pelvis  the 
sciatic  artery  gives  branches  to  the  rectum,  neck  and  base  of  bladder,  prostate 
gland,  and  muscle-  of  the  floor  of  the  pelvis.  Outside  the  pelvis  the  sciatic 
artery  gives  anastomotic  and  coccygeal  branches,  which  run  through  the  great 
sacro-sciatic  ligament  to  the  back  of  the  coccyx,  and  inferior  gluteal  branches 
(which  are  three  or  four)  to  the  Gluteus  maximus.  and  muscular  branches  to 
the  muscles  on  the  back  of  the  hip.  It  sends  articular  branches  to  the  hip-joint 
and  comes  nekyi  ischiadici  to  the  great  sciatic  nerve.  The  uterine  branch 
runs  to  the  cervix  of  the  uterus  and  then  along  its  sides  in  the  broad  ligament 
to  anastomose  with  the  ovarian.     This  artery  is  above  and  in  front  of  the  ureter. 

The  Relations  of  the  Common  Iliac  Arteries.  (Plates  LXXII-XCI.)  The 
right  common  iliac  artery  has  the  following  relations: 

In  Front. — (1)  Peritoneum,  (2)  Small  intestine,  (3)  Sympathetic  nerves, 
and  (4)    Ureter. 

Behind.— (1)  Fourth  and  fifth  lumbar  vertebrae,  (2)  Right  common  iliac 
vein,  (3)   Lef1  common  iliac  vein. 

Outer  Side. — (1)  Vena  cava.  (2)  Right  common  iliac  vein,  (3)  Psoas 
muscle. 

Inner  Side.— (1)  Left  common  iliac  vein. 

The  Left  Common  Iliac  Artery  has  the  following  relations: 

I\  Front.-  (1)  Peritoneum,  (2)  Small  intestine,  (3)  Sympathetic  nerves, 
I     Superior  hemorrhoidal  artery.  (5)    Ureter. 

Behind."  (1)  Fourth  and  fifth  lumbar  vertebra?,  (2)  Left  common  iliac 
vein. 

( >i  m.i;  Side.  —  Psoas  magnus  muscle. 

Iwi.i;  Side.     Left  common  iliac  vein. 

The  Relations  of  the  Internal  Iliac  Artery.— (Plates  LXXII-XCT.) 

In  Front. — (1)   Peritoneum,  and  (2)   Ureter. 

Behind. — (1)  Interna]  iliac  vein,  (2)  Lumbo-sacral  cord.  (3)  Pyriformis 
muscle. 

(  )ii  i;i;  Side.—  Psoas  magnus. 

The  Relations  of  the  External  Iliac  Artery.     (Plate  XCI.) 


ANATOMY    IN    A    NUTSHELL. 


175 


In  Front. — (1)  Peritoneum,  (2)  Intestines,  (3)  Fascia,  (4)  Lymphatic 
vessels,  (5)  Lymphatic  glands,  (6)  Spermatic  vessels,  (7)  Genito-crural  nerve 
(genital  branch.)  (8)  Deep  circumflex  iliac  vein. 

Behind. — (1)  External  iliac  vein,    _     Psoas  magnus. 

Outer  Side. — (1)  Psoas  magnus,  (2)   Iliac  fascia. 

Inner  Side. — (1)  External  Iliac  vein,  (2)  vas  deferens  near  Poupart's  lig- 
ament. 

PLATE  LXII. 


Tin.  Three  Plantah  1  m  i  rossi  i. 


LESSON   XLVII. 

The  external  iliac  artery  passes  from  its  origin,  which  i-  a1  the  lumbo-sacral 
articulation,  along  the  inner  border  of  the  Psoas  magnus  muscle  to  pass  under 
Poupart's  ligamenl  after  which  it  is  called  the  common  femoral  artery.  11 
gives  branches  to  the  Psoas  magnus  and  the  lymphatic  nodes.  The  deep  epi- 
gastric is  a  branch  of  this  artery  and  after  descending  i<>  Poupart's  ligamenl  it 


176  ANATOMY    IN    A    NUTSHELL. 

lies  between  the  peritoneum  and  the  transversalis  fascia.  After  passing  under 
the  vas  deferens  in  the  male  or  the  round  ligament  in  the  female  it  curves  around 
the  lower  and  inner  margin  of  the  internal  abdominal  ring,  then  ascending  it 
pierce-  the  transversalis  fascia  and  the  sheath  of  the  Rectus  muscle  to  enter 
inin  the  longesl  arterial  anastomosis  in  the  body  by  anastomosing  with  the 
superior  epigastric  branch  of  internal  mammary  artery.  It  gives  the  cremas- 
ii.i.ii  branch  t<>  the  Cremasteric  muscle  on  spermatic  cord,  pubic  branch  to 
the  hack  of  the  pubes,  and  MUSCULAR  branches  to  the  adjacent  muscles  and 
integument. 

The  deep  circumflex  iliac  artery  is  also  a  branch  of  the  external  iliac  and 
alter  passing  along  Poupart's  ligament  to  the  anterior  superior  spine  it  con- 
tinues to  the  crest  of  the  ilium.  The  femoral  artery  is  a  continuation  of  the  ex- 
ternal iliac  and  passes  through  the  middle  of  Scarpa's  triangle  just  internal  to 
the  head  of  the  femur.  This  artery  is  an  inch  or  two  in  length  and  here 
it  gives  off  the  profunda  artery  and  continues  as  the  superficial  femoral.  The 
superficial  femoral  passes  to  the  apex  of  Scarpa's  triangle  then  through  Hunter's 
canal,  and  after  passing  through  an  opening  in  the  Adductor  magnus,  at  the 
junction  of  the  middle  and  lower  third  of  the  thigh  close  to  the  bone,  it  is  called 
the  popliteal  artery. 

Scarpa's  triangle. — (Plate  LXXIV.)  is  bounded  above  by  Poupart's  lig- 
ament, externally  by  the  Sartorius  muscle,  and  internally  by  the  Adductor 
longus.  Its  floor  is  formed  from  without  inward  by  the  Iliacus,  Psoas, 
Pectineus,  Adductor  brevis  (?)  and  Adductor  longus.  The  femoral  vein 
lies  "ii  the  inner  side  of  the  femoral  artery  and  the  anterior  crural  nerve  lies  on 
ii<  outer  side.     Lymphatics  and  fat  are  behind  the  nerve. 

Hunter's  canal.— (Plates  LXIV-LXXVUI.)  occupies  the  middle  third  of 
the  thigh,  while  Scarpa's  triangle  occupies  the  upper  third.  This  canal  is 
bounded  externally  by  the  Vastus  internus  and  antero-internally  by  ax 
aponeurosis  passing  from  the  Vastus  internus  to  the  Adductor  longus  and 
magnus  which  form  its  posterior  boundary.  This  aponeurosis  has  above  it 
the  Sartorius.  The  femoral  vessels  and  long  saphenous  nerve  pass  through 
tins  canal.     The  nerve  is  external  to  and  the  vein  postero-external  to  the  artery. 

The  Relations  of  the  Common  Femoral  Artery.  (Plates  LXXII-LXIV- 
LXVIII-) 

[n  Front.-  (1)  Skin,  (2)  Superficial  fascia,  (3)  Superficial  inguinal  glands, 
(4)  Iliac  portion  of  fascia  lata,  (5)  Prolongation  of  transversalis  fascia,  (6) 
Crural  branch  of  genito-crural  nerve,  (7)  Superficial  circumflex  iliac  vein,  (8) 
Superficial  epigastric  vein. 

Behind. — (1)  Prolongation  of  fascia  covering  Iliacus  muscle,  (2)  Pubic 
portion  of  fascia  lata,  (3)  Nerve  to  Pectineus,  (4)  Psoas  muscle,  (5)  Pectineus 
muscle.  (6)  Capsule  of  hip-joint. 

OUTEB  SlDE.      (1)    Anterior  crural  nerve,  (2)   Small  part  of  Psoas  muscle. 

Inner  Side. — Femoral   vein. 

The  Relations  of  the  Superficial  Femoral  Artery.     (Plates  LXXII-LXIV.) 

In  Front.     (1)   Skin,  (2)   Superficial  and  deep  fasciae,  (3)   Internal  cutane- 


PLATE  LXIII. 


TWELFTH  THORACIC 


EXTERNAL   CUTANEOUS 


SOLEUS 

TIBIALIS   POSTICUS 

FLEXOR  LONGUS  DIGITORUM 
FLFXriR   LONGUS  HALLUCIS 


THE  TWO  INNER 
LUMBRICALES. 
FLEXOR    BREVIS 
.HALLUCIS. 
ABDUCTOR 
MINIMI     OIGITI. 
THE  TWO  OUTER 
LUMBRICALES 
FLEXOR  ACCESSORIUS 

FLEXOR  BREVIS 
MINIMI    OIGITI 

SEVEN  INTEROSSEI. 
ACO.  TRANS.  HALLUCIS. 
AOD.  npi  .    HALtuClS. 


Lumbar,  Sacral  and  Coccygeal  Plexuses. 
177 


178  ANATOMY    IN    A    NUTSHELL. 

mis  nerve,  (4)  Sartorius  muscle,  (5)  Aponeurostic  covering  of  Hunter's  canal, 
(6)    Internal  saphenous  nerve. 

Behind.— (1)  Femoral  vein,  (2)  Profunda  artery.  (3)  Profunda  vein,  (4) 
Pectineus  muscle,  (5)  Adductor  longus,  (6)  Adductor  magnus. 

Outer  Side.— (1)  Long  saphenous  nerve,  (2)  Nerve  to  Vastus  interims, 
,::     Vastus  internus,  (4)   Femoral  vein  (below.) 

Inner  Side. — (1)  Adductor  longus,  (2)  Adductor  magnus,  (3)  Sartorius. 

The  Relations  of  the  Profunda  Artery.     (Plates  LXXII-LXIV.) 

I\  Front. — (1)  Femoral  vein.  (2)  Profunda  vein,  (3)  Superficial  femoral 
arten\  (4)  Adductor  longus  muscle. 

Behind.  (1)  Qiacus,  (2)  Pectineus,  (3)  Adductor  brevis,  (4)  Adductor 
magnus. 

Outer  Side.— Vastus  internus. 

1  \\  ER  SlDE.-     Pectineus. 

The  Relations  of  the  Popliteal  Artery.     (Plates  LXXII-LXIX-LXX.) 

In  Front. — (1)   Femur,  (2)   Ligamentum  posticum,  (3)   Popliteus. 

Behind. — (1)  Semimembranosus,  (2)  Fascia,  (3)  Popliteal  vein,  (4)  In- 
ternal popliteal  artery,  (5)  Gastrocnemius,  (6)   Plantaris,  (7)  Soleus. 

Outer  Side. — (1)  Biceps,  (2)  Outer  condyle.  (3)  Gastrocnemius  (outer 
head,)   (4)   Plantaris,  (5)   Internal  popliteal  nerve  (above.) 

Inner  Side.  —  (1)  Semimembranosus.  (2)  Internal  condyle.  (3)  Gas- 
trocnemius  (inner  head.) 


LESSOX  XL VI II. 

The  branches  of  the  common  femoral  artery  are,  (1)   superficial  epigastric, 

_'    superficial  circumflex  iliac,  (3)  superficial  external  pudic,  (4)  deep  external 

pudic.     The  branches  of  the  superficial  femoral  are,  (1)   muscular  branches,  (2) 

anastomotica  magna.     The  branches  of  the  profunda  femoral  are,  (1)   internal 

circumflex,  (2)  external  circumflex.  (3)   perforating. 

The  superficial  epigastric  artery  passes  through  the  saphenous  opening  and  . 
ascends  almost  to  the  umbilicus,  lying  in  the  superficial  fascia  on  the  external 
oblique  muscle.  It  anastomoses  with  branches  of  the  deep  epigastric  artery. 
The  superficial  circumflex  iliac  artery,  after  piercing  the  fascia  lata,  runs  to  the 
anterior  superior  spine  and  crest  of  the  ilium  below  Poupart's  ligament.  It 
anastomoses  with  the  deep  circumflex  iliac  and  with  the  gluteal  and  external 
circumflex  arteries.  The  superficial  external  pudic  artery,  also  called  superior, 
passes  through  the  saphenous  opening  across  the  spermatic  cord  in  the  male 
and  round  ligament  in  the  female  to  the  lower  part  of  the  abdominal  wall,  penis, 
scrotum  in  the  male,  and  the  labium  in  the  female.  It  anastomoses  with 
branches  of  the  internal  pudic.  The  deep  external  pudic  artery,  also  called  in- 
ferior, crosses  the  Pectineus  muscle  then  pierces  the  fascia  lata  to  pass  to  the 
slrin  of  perineum  and  scrotum  in  the  male  or  labium  in  the  female.  It  anasto- 
moses with  branches  of  superficial  perineal  artery.  The  muscular  branches  of 
the  superficial  femoral  artery  vary  in  number  from  two  to  seven  and  go  mainly 
to  the  Sartorius  and  Vastus  internus  muscles.     The  anastomotica  magna  which 


PLATE  LXIV 


SUPERFICIAL  EPIGASTR 


SUPERFICIAL  EXTERNAL  PUDIC  ARTERr 


ADDUCTOR  BREVIS 


DEEP  EXTERNAL  PUDIC 

SCROTUM 


JNTERNAL  OR  LONG   SAPHENOUS 


ANASTOMOTICA      MAGNA 


ANASTOMOTICA      MAGNA 


SUP.     INT.     ANTICULAR 


INF.  INT     ARTICULAR    A 


SUPERFICIAL  CIRCUMFLEX  ilIAC 
ANT   CRUAL       NERVE 
COMMON   FEMORAL 
FEMORAL    VEIN 


EXTERNAL     CIRCUMFLEX 


-  ILIO-TIBIAL  BAND  OF  FASCIA  LATA 


SUP.  EXT.  ARTICULAR    A. 


INF.  EXT.  ARTICULAR     A. 


Common,  Superficial  and  Profunda  Femoral  Arteries. 

179 


ISO  ANATOMY    IN    A    NUTSHELL. 

arises  near  the  end  of  the  femoral  divides  into  a  superficial  branch  which  passes 
with  the  long  saphenous  nerve,  and  adeep  branch  which  runs  in  front  of  the 
tendon  of  the  Adductor  magnus  to  the  inner  side  of  the  knee-joint,  where  it 
anastomoses  with  the  anterior  tibial  recurrent  and  the  superior  internal  artic- 
ular arteries.  The  profunda  artery  itself  passes  behind  the  superficial  femoral 
vessels  od  the  inner  side  of  the  femur  and  then  behind  the  Adductor  longus  to 
pierce  the  Adductor  magnus  at  the  lower  third  of  the  thigh.  This  is  sometimes 
called  the  fourth  perforating  branch.  The  internal  circumflex  of  the  profunda 
passes  between  the  Psoas  magnus  and  the  Pectineus  to  the  upper  border  of  the 
Adductor  brevis,  at  this  point  it  sends  one  branch  inward  to  the  Adductor 
muscles  and  another  branch  downward  under  the  Adductor  brevis.  The  in- 
ternal circumflex  artery  itself  now  passes  between  the  Quadratus  femoris  and 
the  Adductor  magnus  to  join  the  crucial  anastomosis  which  is  formed  by  the 

[NTERNAL   CIRCUMFLEX    ARTERY,   THE    EXTERNAL   CIRCUMFLEX   ARTERY   and   THE 

Si  periob  perforating  all  of  which  are  branches  of  the  profunda,  and  the 
BCIATIC  arter*s  which  is  one  of  the  terminal  branches  of  the  anterior  trunk  of 
the  internal  iliac.  The  external  circumflex  of  the  profunda  passes  outward 
under  the  Sartorius  and  Rectus  muscles  where  it  divides  into  ascending  branches, 
descending  branches,  transverse  branches.  The  ascending  branches  run  up- 
ward under  the  Tensor  vagina  femoris.  The  descending  branches  run  under 
the  Rectus  as  far  asthe  kneeto  enter  into  the  circumpatellar  anastomosis.  The 
trans^  erse  branches  pass  outward  over  the  Crureus  muscle  and  through  the 
Vastus  externus  to  the  back  of  the  thigh  to  enter  into  the  crucial  anastomosis. 
This  external  circumflex  artery  passes  between  the  anterior  and  posterior  divis- 
ions of  the  anterior  crural  nerve.  The  three  perforating  branches  of  the  pro- 
funda pierce  the  tendon  of  the  Adductor  magnus  to  reach  the  back  of  the  thigh. 
The  supeRiob  ONE  passes  above  the  Adductor  brevis  to  join  the  crucial  anas- 
tomosis. The  middle  one  pienes  the  Adductor  brevis.  The  inferior  one 
passes  below  the  Adductor  brevis. 

The  popliteal  artery  is  a  continuation  of  the  femoral  and  passes  through  the 
popliteal  space  downward  and  outward.  At  the  lower  border  of  the  Popliteus 
mi  scle  it  gives  off  the  anterior  tibial  artery  and  continues  as  the  posterior  tibial 
artery. 

The  popliteal  space  lies  b<  hind  the  knee-joint  and  is  diamond  shaped.    This 

-pace  has    \   FLOOR,  A  ROOF,  and  LATERAL  BOUNDARIES.       It  IS  bounded  above  the 

knee-joinl  externally  by  the  Biceps,  and  below  the  joint  by  the  Plantaris  and 
the  outer  h<  ad  of  the  Gastrocnemius.  It  is  bounded  above  the  joint  internally 
by  the  Sen  in  <  1 1  branosus  and  below  the  joint  by  the  inner  head  of  the  Gas- 
trocnemius, lis  floor  is  formed  by  bones,  ligament  and  muscle.  The  bones 
are  the  femur  and  tibia,  the  ligament  is  the  posterior  ligament  of  the  knee-joint, 
and  the  muscle  is  the  Popliteus.  The  popliteal  artery  passes  obliquely  across 
the  spa<  e  b<  ing  surrounded  by  popliteal  nodes,  and  has  the  articular  branch  of 
the  obturator  nerve  lying  upon  it.  The  popliteal  veins  are  superficial  and  ex- 
ternal to  the  artery.  An  articular  filament  of  the  great  sciatic  nerve  is  often 
found  deep  in   this  space.      The  internal  popliteal  or  popliteal  nerve  crosses  all 


PLATE  LXY 


GEMEUiJS 


If fJ  ^'^4~  INFERI0R  GLorEAL- 


CRUREUS 
SHORT  HEAD    OF    BICEPS 

PUNTARIS 


SUPERIOR  GLUTEAL 


Of   GASTROCNEMIUS 


Muscles  in  thk  Gluteal  Region  and  Back  of  Thigh. 


181 


182  ANATOMY    IN    A    NUTSHELL. 

these  structures  superficially  in  the  median  lint',  and  the  external  popliteal  or 
peroneal  nerve  lies  close  to  the  tendon  of  the  Biceps. 

The  branches  of  the  popliteal  artery  are,  (1)  cutaneous  branches,  three  in 
number  which  descend  in  the  median  line  and  on  each  side  run  across  the  Gast- 
rocnemius  to  the  calf  of  the  leg.  These  branches  may  arise  from  other  branches. 
(•_»)  Superior  muscular  branches,  two  or  three  in  number  pass  to  the  Vastus 
externus  ami  flexors  of  the  thigh.  (3)  Inferior  muscular  or  sural  branches 
generally  two  branches  pass  to  the  Gastrocnemius  and  Plantaris  muscles.  (4) 
Superior  internal  articular  branch  which  passes  under  the  tendon  of  the  Ad- 
ductor magnus  muscle  divides,  one  of  the  branches  joining  the  superior  external 
articular  artery  and  the  other  branch  joining  the  anastomotic^  magna  and  the 
inferior  internal  articular  artery.  (5)  Superior  external  articular  artery  which 
passes  above  the  outer  condyle  under  the  tendon  of  the  Biceps  divides  into  a 
dt  ep  branch  which  joins  the  inferior  internal  articular  artery,  and  anastomotic^ 
magna  artery  and  a  superficial  branch  which  joins  the  inferior  external  artic- 
ular and  the  descending  branch  of  the  external  circumflex  artery.  (6)  The 
azygos  articular  pierces  the  posterior  ligament  of  the  knee-joint  to  supply 
thai  joint.  (  7)  Inferior  internal  articular  passes  below  the  inner  tuber- 
osity of  the  tibia  under  the  internal  lateral  ligament  to  join  the  inferior  external 
and  superior  internal  articular  arteries.  (8)  Inferior  external  articular  artery 
passes  above  the  fibula  under  the  tendon  of  the  Biceps  and  external  lateral 
ligament  to  join  the  anterior  tibial  recurrent  ami  the  inferior  internal  articular 
and  the  superior  external  articular  arteries. 

The  circumpatellar  anastomosis  (Plates  LXXII-LXXYI)  is  formed  by 
the  (1)  superior  external  articular,  (2)  superior  internal  articular,  (3)  inferior 
external  articular.  (4)  inferior  internal  articular,  (5)  fourth  perforating  or 
terminal  branch  of  the  profunda,  (6)  anastomotica  magna,  (7)  descending 
branch  of  the  external  circumflex,  and  (8)  the  anterior  tibial  recurrent.  This 
anastomosis  has  superficial  and  deep  portions.  If  we  substitute  in  this  anas- 
tomosis the  fourth  perforating  or  terminal  branch  of  the  profunda  for  the  pos- 
terior tibial  recurrent  and  azygos  articular,  we  will  have  the  blood  supply  to 
the  knee-joint. 


LESSON  XLIX. 

The  anterior  tibial  artery  (Plates  LXXII-LXXVI)  runs  forward  between 
the  two  heads  of  the  Tibialis  posticus  above  the  interosseous  membrane.  It 
now  descends  on  the  anterior  surface  of  this  membrane  and  crosses  the  anterior 
surface  of  the  tibia  distally  and  the  anterior  ligament  of  the  ankle-joint.  Below 
this  joint  it  i-  called  dorsalis  pedis  artery.  The  branches  of  the  anterior  tibial 
artery  are,  I  muscular,1  which  go  to  the  muscles  of  the  leg.  (2)  Posterior 
tibial  recurrent  branch  (which  i>  not  always  present  |  passes  under  the  Popliteus 
muscle.  (3)  Superior  fibular  branch  which  passes  around  the  neck  of  the  fibula 
and  through  the  Soleus  muscle  to  the  Peroneus  longus.  (4)  Anterior  tibial 
recurrent  which  passesupward  through  the  Tibialis  anticus  to  go  to  the  circum- 
patellar anastomosis.    (5)    Internal  malleolar  branch  passes  under  the  tendons 


PLATE  LXVI. 


SUPERFICIAL  EPIGASTRIC 
SUPERFICIAL  INGUINAL  NODES 


SUPERF.CIAL 

CIRCUMFLEX  ILIAC    VEIN. 


EXTERNAL    FEMORAL 
CUTANEOUS  VEIN 


Superficial  Lymphatic  Vessels  \\i>  Veins  <>f  Leg 

183 


184  ANATOMY    IN    A    NUTSHELL. 

of  the  Extensor  proprius  hallucis  and  Tibialis  anticus  to  the  inner  malleolus. 
6)  The  cMcrnal  malleolar  passes  under  the  tendons  of  the  Extensor  longus 
digitorum  and  Peroneus  tertius  to  the  outer  malleolus. 

The  Relations  of  the  Anterior  Tibial  Artery. 

l.\  Front.-  -(1)  Integument,  (2)  Superficial  and  deep  fascia,  (3)  An- 
terior tibial  nerve,  (4)  Tibialis  anticus  (overlaps  it  in  the  upper  part  of  the  leg), 
(5)  Extensor  longus  digitorum  (overlaps  it  slightly,)  (6)  Extensor  proprius 
hallucis  (overlaps  it  slightly).  (7)  Anterior  annular  ligament. 

BEHIND. — (1)  Interosseous  membrane,  (2)  Tibia,  (3)  Anterior  ligament 
of  ankle-joint. 

Outeb  Side. — (1)  Anterior  tibial  nerve,  (2)  Extensor  longus  digitorum, 
(3)    1  Jxtensor  proprius  hallucis. 

Iwii;  Side. — (1)  Tibialis  anticus,  (2)  Extensor  proprius  hallucis  (crosses 
it  at  it-  lower  part). 

The  dorsalis  pedis  artery  (Plates  LXXII-LXXYI.)  is  the  continuation  of 
the  anterior  tibial.  It  passes  along  the  inner  side  of  the  foot  from  the  ankle- 
joint  to  the  first  intermetatarsal  space,  where  it  divides  into  dorsalis  hallucis 
artery  and  the  communicating  artery.  The  dorsalis  hallucis  artery,  also  called 
firsi  dorsal  interosseous,  passes  in  the  first  interosseous  space  to  the  base  of  the 
mvat  toe  where  it  divides  into  two  branches  which  pass  to  the  dorsal  aspect  of 
the  adjacent  sides  of  the  great  and  second  toes.  Prior  to  this  division  it  gives 
off  a  branch  which  passes  under  the  Extensor  proprius  hallucis  tendon  and  runs 
along  the  dorsal  aspect  of  the  inner  side  of  the  great  toe.  The  communicating 
branch,  also  called  the  plantar  digital,  passes  between  the  two  heads  of  the  First 
dorsal  interosseous  muscle  to  join  the  external  plantar  artery,  thus  completing 
the  plantar  arch,  it  now  gives  off  the  arteria  princeps  hallucis  which  runs 
along  the  plantar  surface  of  the  first  interosseous  space  and  divides  at  the  base 
of  the  toes  into  two  branches  for  the  plantar  aspect  of  the  sides  of  the  great  toe. 
Besides  these  terminal  branches  it  gives  off  (1)  external  tarsal,  (2)  internal 
tarsal.  These  branches  run  outward  and  inward  across  the  cuboid  and  scaphoid 
bones.  (3)  Metatarsal  which  passes  across  the  base  of  the  metatarsal  bones  ex- 
ternally.  This  artery  gives  off  three  interosseous  arteries  which  pass  in 
the  three  outer  interosseous  spaces  to  the  base  of  the  toes  where  they  divide 
into  internaland  external  branches  for  the  dorsalaspect  of  adjacentsides  of  the 
four  outer  toes.  The  outer  interosseous  branch  before  its  division  at  the  base 
ofthetoes  sends  :i  branch  along  the  dorsal  aspect  of  the  outer  side  of  the  little 
toe.  These  three  arterieseach  receives  aposterior  perforating  branch  from  the 
plantar  arch  a1  the  base  of  the  space,  also  an  anterior  perforating  branch  from 
the  digital  artery  ;it   the  front  of  the  space. 

The  Relations  of  the  Dorsalis  Pedis  Artery. 

I\  Front.  (1)  [ntegument,  (2)  Fascia,  (3)  Anterior  annular  ligament, 
I     Innermost   tendon  of  Extensor  brevis  digitorum. 

Behind.-    (1)   Astragalus,  (2)   Navicular,  (3)  Middle  cuneiform,    (4)  The 

ligament-    to    these    bones. 

Outeb  Side. — (1)    Extensor  longus  digitorum,    (2)   Anterior  tibial   nerve. 
Iwii;  Side.     Extensor  proprius  hallucis. 


ANATOMY  IN  A   NUTSHELL. 

LESSON  L. 


185 


The  posterior  tibial  artery  (Plates   LXIX-LXX)  is  a  continuatioD  of  the 
popliteal  artery  and  commences  at  the  lower  border  of  the  Popliteus  muscle, 

from  here  it  passes  to  the  interval  between  the  heel  and  the  internal  malleolus 

PLATE  LXVII. 


v :  Jii 


External  or  Shout  Sapiienoi  s  Vein. 

where  it  divides  into  the  internal  and  external  plantar  arteries.  Along  its 
course  it  lies  upon  the  Tibialis  posticus.  Flexor  longus  digitorum,  tibia,  and 
ankle-joint.     The  branches  of  the  posterior  tibial  artery  are.  (1)   The  peroneal 


186  ANATOMY    IN    A    NUTSHELL. 

artery  which  arises  about  an  inch  below  the  Popliteus  and  passes  along  the 
inner  side  of  the  fibula  to  the  lower  third  of  the  leg  where  it  divides  into  an 
anterior  and  posterior  peroneal.  The  peroneal  artery  itself  gives  off  (a)  mus- 
culab  branches  to  the  muscles  at  the  hack  and  outer  side  of  the  leg,  (b)  nutri- 
ent to  fibula,  (c)  INTERIOR  PERONEAL  which  runs  through  the  interosseous 
membrane  and  then  descends  to  the  outer  ankle,  (d)  Communicating  branch 
runs  inward  to  unite  with  a  similar  branch  of  the  posterior  tibial,  (e)  Pos- 
terior PERONEAL  continues  with  the  main  artery  to  the  outer  side  of  the  os 
calcis.  (f)  The  external  calcanean  sends  several  branches  to  the  outer 
side  of  the  heel.  (2)  Muscular  branch*  s  which  pass  to  the  muscles  on  the  back 
of  the  leg.  (3)  Nutrient  to  the  tibia.  This  branch  also  gives  off  muscular 
branches.  (4)  Communicating  branch  which  runs  across  the  tibia  and  unites 
with  a  similar  branch  from  the  peroneal.  (5)  Internal  calcanean  which  sends 
several  branches  to  the  internal  side  of  the  heel. 

Flu  external  plantar  artery  (Plates  LV-LVI-LVIII)  passes  between  the 
Flexor  brevis  digitorum  and  Flexor  accessorius  to  the  base  of  the  fifth  meta- 
tarsal bone.  It  now  bends  inward  and  arches  across  the  bases  of  the  fourth, 
third,  ami  second  metatarsals  to  the  interval  between  the  second  and  first  meta- 
tarsal,  where  it  joins  the  communicating  branch  of  the  dorsalis  pedis  to  com- 
plete the  plantar  arch.  The  branches  of  the  external  plantar  are  (1)  posterior 
perforating:  which  are  three  in  number  and  run  between  the  heads  of  the  three 
outer  Dorsal  mterossei  to  join  the  interosseous  branches  of  the  metatarsal 
arteries.  (2)  Digital  branches  are  four.  The  first  runs  along  the  outer  side  and 
plantar  aspect  of  the  little  toe,  the  outer  branches  run  along  the  three  outer  in- 
terosseous spaces  to  the  base  of  the  toes  where  each  one  sends  an  anterior  per- 
forating  branch  to  join  an  interosseous  branch  of  the  metatarsal,  and  then 
divides  into  two  brandies  for  the  adjacent  sides  and  plantar  aspects  of  the  toes. 

The  internal  plantar  artery  (Plates  LV-LVI-LVIII)  passes  above  the  Ab- 
ductor hallucis,  then  between  it  and  the  Flexor  brevis  digitorum,  and  from  here 
along  the  inner  side  of  the  great  toe  to  anastomose  with  the  digital  branch  from 
the  princeps  hallucis. 

The  Relations  of  the  Posterior  Tibial  Artery. 

1\  Front. — (1)  Tibialis  posticus,  (2)  Flexor  longus  digitorum,  (3)  Tibia, 
I     Ankle-joint. 

Behind.  (1)  Integument,  (2)  Fascia.  (3)  Gastrocnemius,  (4)  Soleus, 
(5     Deep  transverse  fascia,  (6)   Posterior  tibial  nerve,  (7)  Abductor  hallucis. 

Outer  Side.     Posterior  tibial  nerve,  lower  two-thirds. 

Inner  Side.     Posterior  tibial  nerve,  upper  third. 

The  Relations  of  the  Peroneal  Artery.      (Plate  LXIX.) 

In  Front,     fit  Tibialis  posticus,  (2)   Flexor  longus  hallucis. 

Behind.     (1)  Soleus,  (2)   Deep  transverse  fascia,  (3)   Flexor  longus  hallucis 

Outer  Side.     (1)   Fibula,  (2)   flexor  longus  hallucis. 

Inner  Side.     Flexor  longus  hallucis. 

Veins. 
The  external    iliac  vein  (Plate  XC)    is  a  continuation  of  the   femoral   vein 


PLATE  LXVIII. 


SPERMATIC       CORD 


PECTINEUS 
ADDUCTOR      LONGUS 


SCROTUM 


OBTURATOR. 
ADDUCTOR   MAGNUS 


SUB- SARTORIAL  PLEXUS 

PATELLAR  BRANCH  OF 
LONG   SAPHENOUS 


INTtHNAL  CUTANEOUS 
SARTORIUS 


LONG  SAPHENOUS. 


THE  ANTERIOR  TIBIAL  ARTERY 
AND  NERVE 


ANT.  ANNULAR  LIG. 


EXTERNAL    CUTANEOUS    NERVI 

ANTERIOR  CURAL  NERVE 
-EMORAL  ARTERY 
FEMORAL  VEIN 


INTERNAL  CUTANEOUS 


EXTERNAL    POPLITEAL     OR  PERONEAL 
MUSCULOCUTANEOUS 


PERONEUS  1LONGUS 


EXTENSOR  LONGUS  DIGITORUM 


CUTANEOUS     BRANCH     OF 
MUSCULO  -CUTANEOUS 


PERONEUS.   BREVIS 


PERONEUS  TERTIUS 


Anterior  View  of  Entire  Lower  Limp.. 
L87 


1SS  ANATOMY    IN"    A    NUTSHELL. 

above  Poupart's  ligament  to  the  sacro-iliac  articulation,  where  it  joins  the  in- 
ternal iliac  vein  to  make  the  common  iliac  vein.  The  right  common  iliac  vein 
is  on  the  outer  side  of  the  right  common  iliac  artery,  but  as  it  passes  upward  it 
goes  behind  the  artery.  The  left  common  iliac  vein  is  on  the  inner  side  of  the 
left  common  iliac  artery  throughout  its  course.  The  radicles  of  the  external 
iliac  vein  arc  the  deep  epigastric  and  the  deep  circumflex  iliac  veins,  and  a 
small  pubic  vein.     The  external  iliac  vein  may  have  one  or  two  valves. 

The  internal  iliac  vein,  which  unites  with  the  external  iliac  vein  at  the 
sacro-iliac  articulation  to  form  the  common  iliac  vein,  lies  at  first  on  the  inner 
side  of  ami  then  behind  the  artery.  It  receives  radicles  corresponding  to  all 
the  branches  of  the  internal  iliac  artery  except  the  umbilical  (hypogastric.) 
Jt  drain-  the  viscera  in  the  pelvis  in  the  following  manner:  (1)  the  internal 
pudlc  vein  receives  radicles  which  corresponds  to  all  the  branches  of  the  internal 
pudic  artery  except  the  dorsal  artery  of  the  penis.  (2)  Around  the  lower  end 
of  the  rectum  there  is  a  hemorrhoidal  plexus  which  is  formed  by  the  hem- 
orrhoidal veins.  (3)  The  blood  which  passes  through  the  superior  hemorrhoidal 
vein  empties  into  the  inferior  mesenteric  vein,  while  the  blood  which  empties 
into  the  middle  ami  inferior  veins  passes  into  the  internal  iliac  vein,  thus  is 
established  a  free  communication  between  the  portal  venous  system  and  the 
general  venous  system.  (4)  The  plexus,  which  surrounds  the  vaginal  mucous 
membrane  and  is  well  developed  near  the  orifice,  and  anastomoses  with  the 
vesical  and  hemorrhoidal  plexuses  before  it  joins  the  internal  iliac  vein.  (5) 
The  plexus  which  lies  at  the  sides  and  upper  angles  of  the  uterus  between  the 
layers  of  the  broad  ligament  is  called  uterine  plexus,  and  it  drains  the  sub- 
stance of  4ie  uterus  and  communicates  with  the  ovarian  veins  before  it  joins 
the  internal  iliac  vein. 

The  common  iliac  veins  are  formed  by  the  external  and  internal  iliac  veins 
at  the  sacro-iliac  articulation  from  which  point  they  ascend  obliquely  upward  to 
the  righl  >ide  of  the  median  line  of  the  spine  between  the  fourth  and  fifth  lum- 
bal- vertebra  where  they  join  one  another  to  form  the  inferior  vena  cava.  The 
right  one,  which  is  more  vertical  than  the  left,  passes  at  first  behind  and  then 
to  the  outer  side  of  the  cuimnon  iliac  artery.  The  left  one,  which  is  more  ob- 
lique  and  longer  than  the  right,  passes,  for  the  most  part,  to  the  right  side  of  the 
left  common  iliac  artery  but  passes  behind  its  artery  above.  Each  of  these 
veins  receives  the  ilio-lumbar  vein  and  occasionally  the  lateral  sacral  vein.  The 
left  one.  in  addition,  receives  the  middle  sacral  vein.  No  valves  are  found  in 
these  veins. 

The  inferior  vena  cava,  (Plate  XC)  which  ends  in  the  lower  and  back  part 
of  the  righl  auricle  of  the  heart  near  the  Eustachian  valve,  has  no  length  above 
the  Diaphragm.  It  passes  from  the  fifth  lumbar  vertebra  where  it  is  formed  by 
the  righl  and  lefi  common  iliac  veins  upward  in  front  of  the  spine  on  the  right 
side  of  the  aorta,  and  in  it>  course  it  passe^  in  a  groove  on  the  posterior  surface 
of  the  liver  and  pierces  the  central  tendon  of  the  Diaphragm.  At  this  point 
it  enters  the  fibrous  pericardium  and  is  partially  invested  by  the  serous  peri- 
cardium. 

The  lumbar  veins,  (Plate  XC)  which  drain  the  structures  of  the  abdominal 


PLATE  LXIX. 


BICEPS 


SUPERIOR   EXTERNAL 
ARTICULAR  ARTERY 

CUTER  HEAD  GASTROCNEMIUS 

A2YG0S  ARTICULAR  ARTERY 

INFERIOR   EXTERNAL 
ARTICULAR   ARTERY 


A' TERIOr  TIBIAL  ARTERY 


w///h  si  ;  &i 

-,POPL'TEAL     I\ 


LEXC.1     LOnUS         HALLUCIS 


PERONEUS  LONGUS 

PERONEAL  ARTERY 

FL£XOR      LONGUS        HALLUCIS 
PEBCMEOUS  LONGUS 

PEROHEOUS     BREVIS 

CONTINUATION     OF 
PERONEAL  ARTERY- 


SUPERIOR      INTERNAL 
ARTICULAR     ARTERY 

INNER  HEAD  GASTROCNEMIUS 
GRACILIS 

SEMI-TENOINOSUS 
SEMIMEMBRANOSUS 

INFERIOR     INTERNAL    ARTICULAR 


POSTERIOR  TIBIAL  NERVE 


FLEXOR  LONGUS  DIGITORIUM 


POSTERIOR  TIBIAL  ARTERY 


INTERNAL    ANNULAR  LIGAMENT" 
TENDO     ACHILLIS 
INTERNAL     CALCANEAL     ARTERY 


Showing  Arteries  and  Nerves  of  Back  of  Leo. 

189 


HJO  ANATOMY    IN    A    NUTSHELL. 

walls  and  the  loins,  arc  four  on  each  side,  and  they  arc  all  connected  by  longi- 
tudinal ascending  lumbar  veins.  This  ascending  vein  passes  in  front  of  the 
transverse  processes  in  the  lumbar  region  and  gives  origin  to  the  azygos  vein 
of  it s  own  side.  The  left  lumbar  veins  pass  behindthe  aorta.  The  pampini- 
form plexus  lies  around  the  spermatic  cord  in  front  of  the  vas  deferens  and  is 
formed  by  the  spermatic  veins  which  drain  the  testis  and  epididymis.  This 
plexus  forms  three  or  four  main  trunks  which  pass  through  the  inguinal  canal 
to  form  two  veins.  These  veins  accompany  the  spermatic  artery  and  finally 
make  one  trunk.  The  SPERMATIC  VEINS  ox  the  right  side  empties  into  the 
inferior  vena  cava,  while  the  one  ox  the  left  side  passes  behind  the  sig- 
moid flexure  to  enter  the  left  renal  vein.     The  one  on  the  right  side  has  a  valve. 

The  plexus  in  the  broad  ligament  near  the  ovary  and  around  the  fallopian 
tube  i>  formed  by  the  ovarian  veins  and  communicates  with  the  uterine  plexus. 
These  ovarian  veins  are  similar  to  tin-  spermatic  veins,  that  is  the  one  on  the 
light  side  empties  into  the  inferior  vena  cava,  while  the  one  on  the  left  side 
empties  into  the  left  renal  vein. 

The  renal  veins  lie  in  front  of  their  companion  arteries  which  is  an  exception 
for  the  veins  below  the  Diaphragm.  The  left  vein  passes  in  front  of  the  aorta 
w  lute  it  empiii  s  into  the  inft  rior  vena  cava  at  a  higher  level  than  the  right,  and 
is  the  longer  of  tin-  two  renal  veins.  Its  radicles  are  the  left  spermatic  or  ovar- 
ian, Li  f1  inferior  phrenic,  and  most  always  the  left  suprarenal. 

The  left  suprarenal  vein  empties  into  the  left  renal  or  phrenic  while  the 
tight  empties  into  the  inferior  vena  cava. 

The  two  superior  phrenic  veins  end  in  the  internal  mammary  vein,  after 
accompanying  the  phrenic  nerve  and  comes  nervi  phrenici  artery.     The  two 
im'i  rior  phrenic  veins  accompany  the  phrenic  arteries  and  join  the  inferior  vena 
cava  on  the  righl  side  and  the  left  renal  V(  in  on  the  left  side. 


LESSON  LI. 

The  hepatic  veins  begin  in  the  liver  in  the  capillaries  of  the  intralobular 
v<  in-  and  form  three  main  v<  ins  which  empty  into  the  inferior  vena  cava  as  it 
lies  in  the  groove  on  the  posterior  surface  of  the  liver.  There  are'  no  valves  in 
these  v<  ins.  The  blood  which  passes  Lhrough  the  portal  vein  goes  through  the 
following  vessels:  those  on  the'  left;  before  it  reaches  the  inferior  vena  cava: 
while  i hoe  i  n  the  righl  represent  the  vessels  used  by  the  Hepatic  artery. 

1.  Portal  vein  1.  Hepatic  artery 

2.  Interlobular  vein  2.   Interlobular  artery 

.'!.  Intralobular  capillary  plexus  3.   Its  own  intralobular  capillaries 

4.  Intralobular  vein  4.    Portal  intralobular  capillary  plexus 

5.  Sublobular  vein  5.   Intralobular  vein 

6.  Hepatic  vein  6.  Sublobular  vein 

7.  Inferior  vena  cava  7.   Hepatic  vein 

8.   Inferior  vena  cava. 
It  will  be  noticed  that  the  blood  which  passe-s  through  the  Portal  vein  and 
t  he  1  h  pat  ic  artery  has  a  similar  route  through  the>  last  five  vessels. 


PLATE  LXX 


SUPERIOR         EXTERNAL 
ARTICULAR      ARTtHT 


POPLITEAL       NERVE 

INFERIOR         EXTERNAL 
ARTICULAR     ARTERY 


ANTERIOR  TIBIAL  ARTERY 


PERONEAL     ARTERY 


PERONEUS      BREVIS  — 
CONTINUATION     OF 
PERONEAL  ARTERY 


SUPERIOR      INTERNAL 
ARTICULAR     ARTEt.v 

POPITEAL    ARTERY. 
POSTERIOR  LIGAM:  ,'T  OF  KNEE 

—     SEMI-MEMBRANOStl* 

INFERIOR     INTERNAL 
ARTICULAR 


POSTERIOR  TIBIAL  ?:ERVE 


POSTERIOR  TIBIAL  ARTERY 


FLEXOR     LONGUS    DIGITORUn 
TIBI4LIS  POSTICUS 
COMMUNICATING  BRANCH 
INTERNAL      ANNULAR  LIGAMENT 

-TEN00     ACHILLIS 
INTERNAL     CALCANEAL     AST^RY 


Showing  Muscles  of  Back  of  Leg. 

191 


192  ANATOMY     IN    A    NUTSHELL. 

The  veins  of  the  lower  extremity  are  divided  into  a  superficial  and  deep  set 
like  those  of  the  upper  extremity,  but  the  valves  are  more  numerous.  The 
superficial  veins  of  the  lower  extremity  lie  between  the  two  layers  of  the  super- 
ficial fascia.  The  veins  on  the  dorsum  of  the  foot  form  a  venous  arch,  which 
has  ii-  concavity  backward.  This  arch  receives  digital  radicles  from  the  dorsum 
of  the  iocs,  and  ii  crosses  the  anterior  extremities  of  the  metatarsal  bones. 
This  arch  ends  externally  in  the  short  saphenous  vein  and  internally  in  the  long 
saphenous. 

The  external  or  short  saphenous  vein  (Plate  LXVII)  is  a  continuation  of 
this  arch  and  ascends  behind  the  outer  malleolus  along  the  outer  border  of  the 
tendo  Achillis,  from  here  it  crosses  to  the  inner  border  in  the  median  line  of  the 
leg  posteriorly  to  perforate  the  deep  fascia  in  the  lower  part  of  the  popliteal 
space  where  it  ends  in  the  popliteal  vein  between  the  two  heads  of  theGastroc- 
nemius.  It  receives  cutaneous  radicles  in  its  course  and  it  sends  a  communi- 
cating branch  from  near  its  end  upward  and  inward  to  the  long  saphenous  vein. 
It  communicates  with  the  dee})  veins  below  and  accompanies  the  external 
saphenous  uerve.      This   vein  has  from  nine  to  fourteen  valves  in  it. 

The  internal  or  long  saphenous  vein  (Plate  LXVI)  is  a  continuation  of  the 
arch  and  ascends  in  front  of  the  internal  malleolus  along  the  inner  side  of  the 
leg.  From  this  point  it  accompanies  the  internal  saphenous  nerve  behind  the 
inner  margin  of  the  tibia  and  at  the  knee  it  runs  backward  behind  the  inner  con- 
dyle of  the  femur.  From  here  it  passes  along  the  inner  side  of  the  thigh  to  pass 
through  the  saphenous  opening  where  it  ends  in  the  femoral  vein  about  an  inch 
and  a  half  below  1'oiipart's  ligament.  It  communicates  with  the  deep  veins 
and  receives  cutaneous  radicles  in  its  course.  It  receives  the  superficial  epigas- 
tric, superficial  circumflex  iliac,  and  external  pudic  veins  at  the  saphenous 
opening.    This  vein  maybe  doubleand  it  has  fromseven  to  twenty  valves  in  it. 

The  deep  veins  of  the  lower  extremity  accompany  their  arteries  and  are 
called  venae  co mites  and  have  numerous  valves.  Yeme  comites  are  not  found 
from  the  knee  to  the  hip.  for  in  this  region  there  is  but  one  vein  for  the  artery. 

The  posterior  tibial  veins  are  formed  by  the  internal  and  external  plantar, 
and  are  joined  by  the  peroneal  veins. 

The  anterior  tibial  veins  accompany  the  anterior  tibial  artery  and  join  the 
posterior  tibial  veins  to  form  the  popliteal  vein. 

The  popliteal  vein  passes  through  the  popliteal  space,  passing  from  the 
lower  to  the  upper  boundary  obliquely  outward  ami  becomes  the  femoral  vein 
at  the  aperature  in  the  Adductor  magnus  muscle.  This  vein  receives  the  ex- 
ternal saphenous  vein,  articular  and  sural  veins. 

The  femoral  vein  accompanies  the  femora!  artery  and  passes  under  the 
artery  from  its  outer  to  its  inner  side.  This  vein  continues  as  the  external 
iliac  after  it  passes  under  Poupart's  ligament.  It  has  four  or  five  valves  and 
receives  radicle-  corresponding  to  the  arterial  branches  and  the  internal  saphen- 
ous vein. 

Talipes  comes  from  two  words,  talus  which  means  ankle,  and  pes  which 
means  foot.  Tin-  deformity,  called  club-foot,  depends  upon  the  contraction  of 
muscles  or  tendons,  and  this  contraction  may  either  be  congenital  or  acquired. 


PLATE  LX.\r. 


LUMBAR   LIGAMENT 


LAST    LUMBAR 
VERTEBRA, 


GREATER 
SACRO-  SCIATIC    LIGAMENT 


RECTUS  TENDON 


RECTUS  TENDON 


GLUTEUS  MEOIUS 


GLUTEUS  MINIMUS 


VASTUS  EXTERNUS 


VASTUS  INTERNUS 


RECTUS  FEMORIS 


ILIO-TIBIAL     BAND 


LIGAMENTUM  PATELLAE 


Showing  Muscles  of  I.wki;  and  Anterior  Part  op  the  Thigh. 

193 


194  ANATOMY    IN    A    NUTSHELL. 

We  have  the  following  forms  of  club-foot:  (1)  Talipes  equinus  in  which  the 
heel  is  elevated  and  the  weight  of  the  body  thrown  upon  the  anterior  portion  of 
the  foot.  (2)  Talipes  calcaneus  in  which  the  patient  walks  upon  the  heel.  (3) 
Talipes  cavus  or  arcuatus  in  which  there  is  an  increased  curvature  in  the  arch  of 
the  foot.  (4)  Talipes  varus  in  which  the  footis  turned  inward  the  patient  walk- 
ing on  the  outer  border.  (5)  Talipes  valgus  (flat  or  splay  foot)  in  which  the 
foot  is  everted  or  distorted  outward.  Combinations  of  these  may  occur,  such  as 
Talipes  equino-varus,  Talipes  ealcaneo-varus,  Talipes  calcaneo-valgus,  Talipes 
equino-valgus.     (Plate  LXXXIX.) 

The  following  are  some  of  the  principal  amputations  of  the  whole  or  part 
of  the  foot.  (1)  Syme's  amputation  is  made  at  the  ankle-joint,  leaving  a  large 
heel  flap  and  removing  the  internal  malleolus  and  the  external  malleolus  and 
sometimes  a  slice  from  the  lower  part  of  the  tibia.  (2)  Roux's  amputation  is 
made  at  the  ankle-joint,  leaving  a  large  internal  flap.  (3)  Pirogoff's  amputa- 
tion is  made  by  removing  all  the  tarsal  bones,  except  the  posterior  part  of  the  os 
calcis,  and  a  thin  slice  from  the  tibia  and  fibula  including  the  two  malleoli.  The 
small  portion  of  the  os  calcis  which  remains  is  then  turned  up  and  united  to  the 
lower  surface  of  the  tibia.  (4)  Sub-astragaloid  amputation  is  made  by  removing 
all  the  bones  of  the  foot  except  the  astragalus.  This  operation  is  rarely  per- 
formed. (5)  Chopart's  amputation  is  made  by  removing  all  the  bones  of  the 
foot  except  the  os  calcis  and  astragulas.  (6)  Lisfranc's  amputation  is  made  by 
removing  all  the  metatarsals  and  phalanges,  but  not  cutting  any  of  the  bones. 
(7)  Hey's  amputation  is  a  modification  of  Lisfranc's  amputation  by  sawing 
through  the  internal  cuneiform  bone.  (8)  Skey's  amputation  is  a  modification 
of  Lisfranc's  amputation  by  sawing  off  the  base  of  the  second  metatarsal  bone. 
A  combination  of  Pirogoff's  and  the  sub-astragaloid  is  Hancock's  amputation. 


LESSON  LI  I. 
Hip-Joint.  (Plate  LXXXII.) 
This  joint  is  a  diarthrodial  joint  and  belongs  to  the  subclass  enarthrodial. 
It  has  five  ligaments.  (1)  The  capsular  ligament,  which  is  very  strong  and 
fibrous,  surrounds  the  brim  of  the  acetabulum,  beingjust  external  to  the  coty- 
loid ligament.  Below  it  is  attached  to  the  neck  of  the  femur  into  the  anterior 
intertrochanteric  line  anteriorly,  to  the  root  of  the  neck  of  the  femur  superiorly, 
and  to  the  middle  of  the  neck  of  the  femur  posteriorly.  It  has  two  sets  of  fi- 
bers, circular  and  longitudinal.  The  circular  are  best  developed  at  the  lower 
and  posterior  part  where  they  form  a  collar  called  the  zona  orbicularis  or  liga- 
ment of  Bertin.  The  longitudinal  fibers  form  the  accessory  ligaments.  Some- 
time- there  is  an  opening  in  the  front  of  the  capsular  ligament  for  the  passage  of 
synovial  membrane  to  form  a  bursa  under  the  Psoas  magnus.  (2)  The  ilio- 
femoral or  V  ligament  is  accessory  to  the  capsular  ligament,  it  is  bifurcated  below 
and  is  connected  to  the  anterior  intertrochanteric  line  at  its  outer  and  inner 
portions  and  it  is  attached  above  to  the  anterior  inferior  spine  of  the  ilium. 
(a)  The  ischio-capsulab  ligament  is  an  accessory  ligament  being  attached 
to  the  ischium  below  the  acetabulum  and  passing  through  the  circular  fibers 


ABDOMINAL  AORTA 


COMMON    ILIAC    A. 

SACRA         MEDIA 
INTERNAL  ILIAC  A. 

EXTERNAL  ILIAC  A. 

OBTURATOR    A. 
SCIATIC    A. 

PUDIC    ARTERY 
INTERNAL        CIRCUMFLEX  A 
SUPERFICIAL  FEMORAL  A. 

PERFORATING 


ANASTOMOTICA      MAGNA 

TERMINAL  BRANCH  OF  PROFUNDA 
ANASTOMOSING     WITH     POPLITEAL 


SUP.    INT.    ANT1CULAR 

INT.    LATERAL    UG. 
INF.  INT.  ARTICULAR 


POPLITEAL 


SOP   EXT.  AflTICULAR 


POST.    TIBIAL  A. 


INT.  MALLEOLAR 

TARSAL    BRANCH 
DORSALIS      PEDIS 

METATARSAL 


PLATE  LXXII. 

DEEP  EPIGASTRIC  A 

LIO  LUMBAR  A. 

DEEP  CIRCUMFLEX  ILIAC  A 

GLUTEAL  A. 
COMMON  FEMORAL 

PROFUNDA  FEMORAL 
EXTERNAL  CIRCUMFLEX 

CRUCIAL  ANASTOMOSIS 


EXT.  LATERAL  LIG, 
INF.  EXT.  ARTICULAR. 

TIBIAL  RECURRENT 


PERONEAL    A. 


EXT.  MALLEOLI 
ANT.     PERONEAL  A. 
POST.    PERONEAL    A. 

EXT.    PLANTAR 


The  Arteries  of  the   Entire  Lower  Extremity 

195 


196  ANATOMY    IN    A    NUTSHELL. 

at  the  lower  and  hack  part  of  the  capsular  ligament,  (b)  The  pubofemoral 
ligament  is  an  accessory  ligament  and  passes  from  the  ilio-pectineal  eminence 
to  the  rough  tubercle  in  fronl  of  the  lesser  trochanter. 

:;  The  ligamentum  teres  passes  from  the  margins  of  the  notch  at  the 
bottom  of  the  acetabulum  to  a  depression  on  the  head  of  the  femur.  It  is 
covered  by  a  n  flection  of  synovial  membrane  and  consists  of  connective  tissue 
and  vessels. 

1 1  The  cotyloid  ligament  surrounds  the  brim  of  the  acetabulum, making 
this  cavity  deeper.  It  is  broad  at  its  point  of  attachment  and  runs  to  apoint, 
thus  making  it  triangular  on  cross  section. 

5)  The  transverse  ligament  is  a  portion  of  the  cotyloid  ligament  which 
crossi  -  the  notch  at  the  lower  portion  of  the  acetabulum.  The  nutrient  vessels 
to  the  joint  pass  under  this  ligament. 

The  synovial  membrane  of  the  hip-joint  is  reflected  over  the  inner  surface 
of  the  capsular  ligament  on  to  the  neck  of  the  femur,  and  from  here  over  to  the 
ligamentum  teres  to  the  bottom  of  the  acetabulum.  At  this  point  it  covers 
some  fat.  As  said  before  it  frequently  communicates  with  the  bursa  which  is 
under  the  Psoas  muscle. 

The  flexors  of  the  hip-joint  are  all  the  muscles  in  the  floor  of  Scarpa's  tri- 
angle, viz..  the  Qiacus,  Psoas  magnus,  Pectineus,  Adductor  brevis,  Adductor 
longus.  The  Sartorius,  the  R(  ctus  and  the  anterior  fibers  of  the  Gluteus  niedius 
and  (  Uuteus  minimus  are  also  flexors  of  the  hip-joint. 

The  extensors  of  this  joint  are  the  Gluteus  maximus,  Biceps,  Semimem- 
branosus, and  Sen  itendinosus. 

'1  Ik  adductors  are  the  Addu<  t<  r  1<  ngus,  Adductor  brevis,  Adductor  magnus 
plus  the  Bic<  ps,  Gracilis,  and  lower  part  of  the  Gluteus  maximus. 

Tin  abductors  of  this  joint  are  the  Gluteus  medius,  and  Gluteus  minimus. 
and  the  up]  <  r  pan  i  f  tin  Glut<  us  maximus. 

Th<  internal  rotators  an  the  anterior  fibers  of  the  Gluteus  medius,  Gluteus 
minimus,  and  T<  nsor  fas<  ia  f<  moris. 

Th(  external  rotators  <  f  this  joint  are  all  the  muscles  in  the  gluteal  region 
excepl  tin  posterior  fibers  cf  the  Gluteus  medius  and  Gluteus  minimus,  plus 
tin   lliacus,   tin  three  Adductors,  the  Feetineus  and  the  Sartorius. 

The  tendino-trochanteric  band  is  a  str<  ngthening  band  of  the  hip-joint. 

Thi  ligamentum  teres  is  an  incorporated  tendon  of  the  P<  ctineus  muscle. 

Neiaton's  line  is  a  line  drawn  fr<  m  the  anterior  superior  spineof  the  ilium 
to  tin    tuberischii. 

Bryant's  triangle  is  a  triangle  mad<  by  N<  lat<  n's  line  and  a  line  drawn  from 
tin   ant*  i  tor  su]  <  i  tor  s]  in<  —  of  the  ilium  whi<  h  nn  <  ts  a  third  line  cor- 

responding to  the  long  axis  of  the  f<  mur  continued. 

Th(  blood  supply  of  the  hip-joint  is  theinternal  circumflex,  gluteal,  sciatic, 
and  ob 

Th<  nerve  supply  is  the  anterior  crural,  the  obturator,  the  obturator  access- 
ory, greal  sciatic,  and  branches  from  the  sacral  plexus. 


PLATE  LXXIII. 


ILIO  INGUINAL 


EXTERNAL 
CUTANEOUS 


The  Diaphragm,  Psoas  Magnus  \m>  Parvus. 
197 


198  ANATOMY    IN    A    NUTSHELL. 


LESSON  LI II. 

Knee-Joint.     (Plates  LXXXIII.) 

The  knee-joint  is  a  diarthrodial  joint  and  belongs  to  the  subclass  ginglymus. 
It  is  a  modified  ginglymus  joint.  This  joint  lias  flexion,  extension,  and  a  slight 
rotation  externally  and  internally. 

Ligainentus  muscles  are  those  that  cross  a  joint,  they  are  also  called  elastic 
ligaments  of  the  joint.  The  ligamentous  muscles  of  the  knee-joint  are  Biceps, 
Quadriceps,  Semimembranosus,  Semitendinosus,  Gracilis,  Sartorius,  Gastrocne- 
mius, Plantaris,  and  Popliteus. 

The  nerve  supply  of  this  joint  is  the  anterior  crural,  the  obturator,  the  in- 
ternal  and  external  popliteal. 

The  blood  supply  of  the  knee-joint  is  the  anastomotica  magna,  the  five 
articular  branches  of  the  popliteal,  the  anterior  and  posterior  tibial  recurrent, 
and  the  terminal  branches  of  the  profunda. 

The  flexors  of  this  joint  are  the  Biceps,  the  Semimembranosus,  Semitendi- 
nous. Gracilis,  Sartorius,  and  indirectly  the  Gastrocnemius,  Popliteus,  and 
Plantaris. 

The  extensors  of  this  joint  are  the  Quadriceps,  plus  outer  rotation  by  the 
Biceps  and  inner  rotation  by  the  Popliteus  and  Semitendinosus,  and  to  a  slight 
degree  by  the  Semimembranosus,  Sartorius  and  Gracilis. 

The  strengthening  bands  are  the  Biceps,  Sartorius,  and  Semimembranosus. 

The  incorporated  tendons  are  the  Peroneus  longus  and  Adductor  magnus. 
The  incorporated  tendon  of  thePeroneus  longus  makesthe  external  lateral  lig- 
ament of  the  knee-joint,  and  that  of  the  Adductor  magnus  makes  the  internal 
lateral  ligament. 

The  knee-joint  is  formed  by  the  condyles  of  the  femur,  the  head  of  the 
tibia,  and  the  patella,  It  has  fourteen  ligaments,  an  external  set  in  which  there 
are  six,  and  an  interna]  set  hi  which  there  are  eight.  The  first  of  the  external 
Ligaments  is  the  anterior  or  ligamentum  patella,  which  is  a  continuation  of  the 
tendon  of  the  Quadriceps  extensor.  (Plate  LXXXIII.)  It  is  attached  above 
to  the  apex  ami  rough  surface  on  the  lower  and  posterior  portions  of  the  patella, 
and  below  it  is  attached  to  the  lower  part  of  the  tubercle  of  the  tibia.  A  bursa 
is  found  bei  w<  en  the  upper  pail  of  the  tubercle  and  the  ligament. 

The  second  ligamenl  of  this  set  is  the  posterior  ligament,  called  the  liga- 
mentum posticum  Winslowii,  which  is  broad  and  thin  and  covers  the  back  of 
the  knee-joint.  (Plate  LXXXVI.)  It  has  a  central  and  two  lateral  portions, 
the  lateral  portion-  are  attached  above  the  condyles  of  the  femur  superiorly, 
and  to  the  head  of  the  tibia  inferiorly.  The  central  portion  which  is  derived 
from  an  expansion  of  the  Semimembranosus  tendon  and  passes  from  the  inner 
tuberosity  of  the  tibia  to  the  inner  side  of  the  upper  part  of  the  outer  condyle 
of  the  femur. 

The  third  ligamenl  ni  thissel  is  the  internal  lateral  ligament,  which  is  broad 
and  flat  and  i-  attached  above  to  the  inner  condyle  of  the  femur  and  below  to 
the  margin  of  the  inner  tuberosity,  to  the  internal  fibro-cartilage,  and  to  the 


PLATK  LXXIY. 


SPERMATIC      CORD 


ADDUCTOR 


GLUTEUS     MEDIUS 


GLUTEUS     MINIMUS 


ILIO-TIBiAL  BANO 
OF  FASCIA  LATA 


\    H       V' 

lIM  LIGAMENTUM 
PATELLAE 


The  .Muscles  ix  Front  of  the  Thigh. 
199 


200  ANATOMY   IN    A    NUTSHELL. 

inner  surface  of  the  shaft  of  the  fibula  extending  one  and  one-half  inches.  (Plates 
LXXXIII-LXXXVL) 

The  fourth  ligamenl  of  this  set  is  the  Ions  external  lateral  ligament,  which 
is  the  divorced  tendon  of  the  Peroneus  longus  and  is  nowa  rounded  cord,  being 
attached  above  to  the  external  condyle  of  the  femur  and  below  to  the  external 
pari  of  the  head  of  the  fibula.  It  divides  the  tendon  of  the  Biceps  into  two 
portions.     (Plates  LXXXIV-LXXXVI.) 

The  fifth  ligament  of  this  set  is  the  short  external  lateral  ligament,  which 
lies  behind  and  almost  parallel  with  the  long  external  lateral  ligament  and  it 
is  very  indistinct,  being  attached  above  to  the  outer  condyle  of  the  femur  and 
below  to  the  styloid  process  of  the  fibula. 

The  sixth  ligament  of  this  set  is  a  capsular  ligament.  It  fills  the  spaces 
left  by  the>e  other  ligaments.  It  is  thin  and  is  attached  to  the  margins  of  the 
articular  surfaces  of  the  bones.  It  blends  with  the  fascia  of  the  thigh  and  re- 
ceives  expansions  from  the  Vast!  muscles  above,  called  lateral  patellar  liga- 
ments.    (Plate  LXXXIII.) 

'The  following  structures  are  on  the  head  of  the  tibia  from  before  backward 
in  the  median  line.     (Plate  LXXXY.) 

1.  Transverse  ligament. 

2.  Anterior  extremity  of  internal  semilunar  cartilage. 

3.  Anterior  crucial  ligament. 

4.  Anterior  extremity  of  external  semilunar  cartilage. 

5.  The  spine  of  tibia. 

6.  Posterior  extremity  of  external  semilunar  cartilage. 

7.  Posterior  extremity  of  internal  semilunar  cartilage. 

8.  Posterior  crucial  ligament. 

The  ligaments  of  the  internal  set  are  eight  in  number. 

The  first  ligament  is  the  anterior  or  external  crucial,  which  is  attached  to 
the  depression  in  front  of  the  spine  of  the  tibia  and  to  the  external  semilunar 
fibro-cartilage.  It  now  passes  upward,  backward,  and  outward  to  the  pos- 
terior  pint  of  the  inner  side  of  the  external  condyle  of  the  femur.  (Plate 
LXXXV.) 

The  second  ligament  of  this  set  is  the  posterior  or  internal  crucial,  which  is 
attached  to  a  depression  behind  the  spine  of  the  tibia,  to  the  popliteal  notch, 
and  also  to  the  posterior  border  of  the  external  semilunar  fibro-cartilage.  From 
here  it  passes  upward,  forward,  and  inward  to  be  attached  to  the  oblique  curve 
of  the  inui  )■  condyle,  to  the  fore  part  of  the  intercondylar  fossa,  also  to  the  an- 
terior  part  of  the  outer  surface  of  the  inner  condyle. 

The  semilunar  fibro-cartilages  help  to  deepen  the  cavities  which  receive 
the  condyle  of  the  femur.  They  are  thicker  at  the  circumference  than  at  the 
central  portion.  The  internal  semilunar  fibro-cartilage  is  longer  antero-pos- 
teriorly  than  transversely.  lis  anterior  extremity  is  attached  in  front  of  the 
anterior  crucial  ligamenl  to  the  tibia  and  the  posterior  extremity  is  attached 
in  front  of  the  posterior  crucial  ligament.  The  external  semilunar  fibro-cartil- 
age is  nearly  circular,  and  its  anterior  extremity  is  attached  in  front  of  the  spine 
to  the  tibia,  its  posterior  extremity  is  attached  to  the  back  of  the  spine.  (Plate 
LXXXV.) 


PLATE  LXXV 


GASTROCNEMIUS 


SOLEUS. 


EXTENSOR   KKUHRIUS  HALLUCIS 


*NT.  ANNULAR  LIG 


DORSAL    INTER02SB. 


\\       ■patIllaCj  '  / 


U  W  v,  V!  V\ 


PERONEUS  LONGUS 


PERONEUS  TERTIUS 


PERONEUS  TERTIUS 


XTENSOR  BREVIS  WGITORUM 


Muscles  ix  Front  oi   Leg. 
201 


202  ANATOMY    IN    A    NUTSHELL. 

The  transverse  ligament  passes  between  the  anterior  extremities  of  the 
semilunar  fibro-cartilages  and  is  a  hand  of  broad  fibers.     (Plate  LXXXIV.) 

The  coronary  ligaments  hold  the  circumferences  of  the  semilunar  fibro- 
cartilages  bo  the  head  of  the  tibia.     (Plate  LXXXIV.) 

The  synovial  membrane  of  the  knee-joint  is  the  largest  in  the  body.  It  ex- 
tends over  two  inches  above  the  joint  under  the  extensor  muscles  and  it  passes 
over  the  crucial  ligaments  to  the  head  of  the  tibia.  It  covers  both  surfaces  of 
the  semilunar  fibro-cartilages  and  lines  the  capsular  ligament.  It  gives  a  cover- 
ing to  the  tendon  of  the  Popliteus  muscle. 

The  ligamentum  mucosum  is  a  fold  of  this  membrane.  It  is  triangular  in 
shape,  being  attached  to  the  intercondylar  notch  and  extending  to  the  patella. 

The  ligamenta  alalia  are  two  processes  of  this  membrane  which  are  on  either 
side  of  the  ligamentum  mucosum. 


LESSON  LIV. 
The  Superior  Tibio-Fibular  Joint. 
This  joint  is  an  arthro dial  joint.     Its  anterior  superior  ligament  extends  from 

the  head  of  the  fibula  upward  and  inward  to  the  external  tuberosity  of  the  tibia. 
Its  posterior  superior  ligament  extends  from  the  back  part  of  the  head  of  the 
fibula  upward  and  inward  under  the  tendon  of  the  Popliteus  muscle  to  the  back 
part  of  the  outer  tuberosity  of  the  tibia.      (Plate  LXXXVI.) 

The  middle  tibio-flbular  articulation  is  formed  by  the  interosseous  membrane 
which  is  attached  to  the  interosseous  ridges  of  the  tibia  and  fibula.  The  fibers 
of  this  membrane  pass  down  from  the  tibia  to  the  fibula.  Above  this  mem- 
brane there  is  an  opening  for  the  anterior  tibial  vessels,  and  below  it  one  for  the 
anterior  peroneal  vessels. 

The  inferior  tibio-flbular  arctiulation  is  a  syndesmosis  joint.  The  inferior 
interosseous  (igament  which  passes  between  the  adjacent  rough  surfaces  of  the 
tibia  and  fibula  is  continuous  above  with  the  interosseous  membrane. 

The  anterior  ligament  of  this  joint  passes  between  the  adjacent  margins  of 
the  tibia  and  fibula  and  is  triangular  in  shape.  The  posterior  ligament  is  a 
similar  hand  posteriorly.  It  is  smaller  than  the  anterior  one.  The  transverse 
or  inferior  ligament  of  this  joint  is  a  narrow  band  which  is  continuous  with  these 
two  ligaments  and  extends  from  the  back  of  the  external  malleolus  nearly  to 
the  internal  malleolus  and  helps  to  deepen  the  ankle-joint.  (Plate  LXXXYII.) 
The  Ankle-Joint.     (Plates  LXXXVII-LXXXVIII.) 

This  joint  is  a  ginglymus  or  hinge-joint,  and  is  formed  by  the  lower  ends 
of  the  tibia  and  fibula  and  the  upper  surface  of  the  astragalus. 

The  anterior  ligament  of  this  joint  is  connected  above  with  the  edge  of  the 
articular  surface  of  the  tibia,  and  below  with  the  margin  of  the  superior  articu- 
lar surface  of  the  astragalus.     This  ligament  is  thin  and  broad. 

The  posterior  ligament  is  attached  above  to  the  transverse  ligament  of 
the  inferior  tibio-fibular  articulation  and  below  to  the  back  of  the  upper  articu- 
lar surface  of  the  astragalus,  most  of  the  fibers  of  this  ligament  are  transverse. 

The  internal  lateral  ligament   is  called  the  deltoid   ligament  and  consists 


PLATE  LXXVI. 


SUPERIOR  INTERNAL 
ARTICULAR  ARTERY 


INFERIOR  INTERNAL 
ARTICULAR  ARTERY 


ANTERIOR  TIBIAL 
RECURRENT  ARTERY 


SUPERIOR  EXTERNAL 
ARTICULAR  APTERY 


INFERIOR   EXTERNAL 
ARTICULAR  ARTERY 


GASTROCNEMIUS 


SOLEUS 


m  i  i 

til  \S  ')°'i^^  l"-i 


LONGUS 


H 


ANTERIOR  TIBIAL  ARTERY 


INTERNAL    MALLEOLAR       ARTERY 


BREVIS 


TERTIUS 


ANTERIOR  PERONEAL  ARTERY 


M     -AfilMLARi. 
>EDIS      ARTERY-       |     [^Hh' 


COMMUNICATING    BRANCH 
DORSALIS    HALLUCIS    ARTERY 


TENDON     OF     EXTENSOR 
BREVIS     DIGITORUM 
TARSAL  BRANCH 
.  METATARSAL  3RANCH 


DORSAL  INTEROSSEUS  ARTERY 


Arteries  and  Nerves  in  Front  of  Leg. 
203 


21)4  ANATOMY    IN    A    NUTSHELL. 

of  two  main  parts.  First  a  superficial  part  which  is  attached  by  its  apex  to  the 
internal  malleolus  and  by  its  base  to  the  inner  side  of  the  astragalus  and  the 
sustentaculum  tali  posteriorly,  while  anteriorly  it  is  attached  to  the  tuberosity 
of  the  scaphoid  and  blends  with  the  inferior  calcaneo-scaphoid  ligament.  The 
second,  a  deep  portion  which  passes  from  the  apex  of  the  malleolus  to  the  side 
of  the  astragalus. 

The  external  lateral  ligament  consists  of  three  portions.  The  first  is  an 
anterior  fasciculus  which  passes  between  the  front  of  the  external  malleolus  and 
the  side  of  the  astragalus  in  front  of  the  superior  articular  process. 

The  second  is  a  middle  fasciculus  which  passes  from  the  apex  of  the  external 
malleolus  to  the  outer  side  of  the  os  calcis. 

The  third  is  a  posterior  fasciculus  which  is  attached  behind  the  deep  groove 
on  the  posterior  part  of  the  outer  malleous  and  from  this  point  passes  inward 
to  a  depression  on  the  posterior  surface  of  the  astragalus. 

The  synovial  membrane  of  the  ankle-joint  lines  the  inner  surfaces  of  its 
ligaments,  and  from  there  it  is  reflected  on  the  two  articular  surfaces  of  the 
hones  forming  the  joint.  It  sends  a  prolongation  into  the  inferior  tibio-fibular 
articulation. 

The  ligamentous  muscles  of  the  ankle-joint  are  all  the  muscles  from  the 
knee  to  the  ankle  except  the  Popliteus. 

The  nerve  supply  is  the  anterior  tibial,  posterior  tibial  and  internal  saphen- 


ous. 


The  blood  supply  is  the  anterior  tibial,  posterior  tibial  and  peroneal. 


LESSOX  l.V. 
Tin.  Joints  of  the  Tarsus.     (Plates  LXXXVII-LXXXVIII.) 
All  these  joints  are  arthrodial  except  the  articulation  between  the  navicu- 
lar and  the  astragalus,  which  is  an  enarthrodia!  joint. 

Till.   LIG  WIE.XTS   BETWEEN  THE  <  >S  CALCIS  AND  THE  ASTRAGALUS  ARE: 

1     Anterior  calcaneo-astragaloid  ligament. 
I    :'      sseous  calcaneo-astragaloid  ligament. 
(3)    Externa]  calcaneo-astragaloid  ligament. 

THE   LIGAMENTS   BETWEEN  THE  OS  CALCIS  AND  SCAPHOID  ARE: 

(1)  Superior  or  dorsal  calcaneo-scaphoid  ligament. 

(2)  Inferior  calcaneo-scaphoid  ligament. 

Ib.TU  l.l.X  THE    ASTRAGALUS  AXH  THE  SCAPHOID  THERE  IS  RUT  ONE  LIGAMENT. 

1  I  The  superior  or  dorsal  astragalo-scaphoid  ligament. 

Till.    LIGAMENTS   BETWEEN   THE   SCAPHOID,   CUBOID,    AND  THE  THREE  CUNEI- 
I  ORM    are: 

(1)   Superior  or  Dorsal  scapho-cuboid  ligament. 
-'    Superior  or  Dorsal  scapho-cuneiform  ligament. 

(3)  Superior  or  Dorsal  intercuneiform  ligament. 
1     Superior  or  Dorsal  cubo-cuneiform  ligament. 

(5)    Internal  lateral  scapho-cuneiform  ligament. 

The  plantar  ligaments  are  similarly  arranged  upon  the  bottom  of  the 
foot. 


PLATE  LXXVII. 


GASTROCNEMIUS 

/        INNER  HEAD 
/ 

7 SEMI-MEM3RAN0SUS 


t — POSTERIOR    TIBIAL  NERVE 


PERONEJS      LONtiUS 


Muscles  in  Hack  of  Leg  (Superficial  Laykkj 
205 


206  ANATOMY    IN    A    NUTSHELL. 

(7)  There  are  four  strong  interosseous  ligaments  passing  between  the  rough 
non-articular  surfaces  of  these  bones. 

THE   LIGAMENTS   BETWEEN  THE  OS  CALCIS  AND  CUBOID  ARE: 

(1)  Superior  or  dorsal  calcaneo-cuboid  ligament. 

Inferior  calcaneo-cuboid  ligament. 

(3)  Internal  calcaneo-cuboid  ligament. 

(4)  External  calcaneo-cuboid  ligament. 

There  is  the  long  calcaneo-cuboid  ligament  also  called  ligamentum  longum 
plantar.  This  ligament  passes  between  the  under  surface  of  the  os  calcis  in 
front  of  the  tuberosities  to  the  posterior  margin  of  the  peroneal  groove  of  the 
cuboid.  Sonic  of  the  fibers  pass  over  the  sheath  of  the  tendon  of  the  Peroneus 
longus  and  are  attached  to  the  bases  of  the  second,  third,  and  fourth  meta- 
carpal  bones. 

The  short  calcaneo-cuboid  ligament  passes  from  the  tubercle  and  depression 
uii  the  under  surface  of  the  os  calcis  to  the  under  surface  of  the  cuboid  behind 
the  peroneal  groove. 

The  Joints  of  the  Tarsus  and  Metatarsus. 

The  ligaments  of  these  joints  are: 

(1)  Dorsal  tarso-metatarsal  ligament. 

(2)  Dorsal  intermetatarsal  ligaments. 

(3)  Internal  lateral  tarso-metatarsal  ligaments. 

(4)  The  plantar  ligaments  are  arranged  irregularly  between  these  bones. 
The  [nterosseous  ligaments  which  are  strong  bands  are  three  in 

number: 

(1)  The  internal  one  passes  from  internal  cuneiform  to  the  second  meta- 
tarsal. 

(2)  The  middle  one  passes  between  the  external  cuneiform  and  the  second 
metatarsal. 

(3)  The  external  one  connects  the  external  cuneiform  and  the  third  meta- 
tarsal. 

There  auk  six  synovial  membranes  of  the  tarsus  and  metatarsus: 

(1)  One  for  the  posterior  calcaneo-astragaloid  articulation. 

(2)  One  for  the  anterior  calcaneo-astragaloid  articulation  and  the  scapho- 
as1  ragaloid  articulation. 

(3)  One  for  the  calcaneo-cuboid  artciulation. 

(4)  ( )ne  for  the  articulation  of  the  scaphoid  and  the  three  cuneiform  bones; 
the  cuneiform  bones  with  each  other;  the  external  cuneiform  and  the  cuboid; 
and  the  middle  and  external  cuneiform  bones  with  the  bases  of  the  second  and 
third  metatarsal  bones. 

<  me  1  >et  ween  the  first  metatarsal  and  internal  cuneiform  bones. 

()'))   One  for  fourth  and  fifth  metatarsal  with  the  cuboid. 

The  bases  of  the  metatarsal  bones  are  joined  by  dorsal,  plantar,  and  in- 
terosseous Ligaments! 

The  digital  ends  are  joined  by  the  transverse  metatarsal  ligament,  which 
connect-  the  firsl  metatarsal  with  the  others,  similar  to  those  in  the  hand. 

The  metatarso-phalangeal  and  phalangeal  articulation  are  similar  to  the 
corresponding  parts  of  the  hand. 


PLATK  LXXVUI- 


GLUTEUS    MINIMUS 
SUPERIOR    GLUTEAL    ARTERY 
SUPERIOR    GLUTEAL        NERVE 

OBTURATOR     INTERNUS 
INFERIOR    GLUTEAL 
SMALL    SCIATIC 
GREAT_  SCIATIC   NERVE 

GLUTEUS  MAXIMUS 


PUDIC     ARTERY 

PUDIC    NERVE. 
nglj —    —SCIATIC     ARTERY 

--  COCCYGEAL  BRANCH 

TUBERISCHII 

INFERIOR  PUDENDAL 
ADDUCTOR  MAGNUS 
DESCENDING  CUTANEOUS 


EXTERNAL    POPLITEAL    OR    PERONEAL 


SOLEUi 


PERONEAL  ARTERY 


GRACILIS 


NTERNAL      POPLITEAL 


POSTERIOR      TIBIAL    NERVE 


SOLEUS 


POSTERIOR  TIBIAL  ARTERY 


INTERNAL  CALCANEAN 
PLANTAR       CUTANEOUS 


Posterior  View  <»k  Entire  Leg. 
207 


208  ANATOMY    IN    A    NUTSHELL. 

LESSON  LVI. 
Lumbar  Plexus.     (Plates  LXIII-LXXIII.) 

The  lumbar  plexus  is  made  of  the  anterior  branches  of  the  first,  second, 
third,  and  a  greater  part  of  the  fourth  lumbar  nerves.  The  twelfth  dorsal 
nerve  scuds  a  communicating  branch  to  the  first  lumbar  nerve.  This  plexus 
lies  in  the  posterior  pari  of  the  Psoas  magnus  muscle  in  front  of  the  transverse 
processes  of  the  lumbar  vertebrae. 

The  first  lumbar  nerve  divides  into  two  branches,  the  ilio-hypogastric  and 
the  ilio-inguinal.  (Plate  LXX11I.)  The  ilio-hypogastric  nerve  passes  through 
the  outer  border  of  the  Psoas  magnus  in  front  of  the  Quadratus  iumborum  and 
behind  the  kidney  and  the  large  intestine.  It  pierces  the  Transversalis  muscle 
at  the  outer  border  of  the  Quadratus  Iumborum  to  enter  the  areolar  tissue  be- 
tween the  transversalis  muscle  and  the  Internal  oblique.  At  this  point  it  fre- 
quently joins  the  last  dorsal  and  inguinal  nerve.  It  divides  into  a  hypogastric 
branch  and  an  iliac  branch.  The  hypogastric  branch  passes  between  the  Trans- 
versalis and  the  Internal  oblique  muscles  forward  and  downward  and  gives 
branches  to  each  of  these  muscles.  It  joins  the  ilio-inguinal  nerve  and  pierces 
the  Internal  oblique  muscle  near  the  anterior  superior  spine  of  the  ilium  and 
passes  beneath  the  aponeurosis  of  the  External  oblique  towards  the  median  line. 
It  pierces  the  aponeurosis  of  the  External  oblique  muscle  about  an  inch  above 
the  externa]  abdominal  ring  and  .becomes  cutaneous  to  supply  the  skin  over  the 
symphysis.  The  iliac  branch  pierces  both  the  Internal  oblique  muscle  and  the 
Externa]  oblique.  The  point  where  it  pierces  the  External  oblique  muscle  is 
above  the  crest  of  the  ilium  a  little  in  front  of  its  middle  portion.  It  supplies 
the  integument  near  the  Gluteus  medius  muscle  and  the  Tensor  fascia  femoris. 
The  ilio-inguinal  nerve  passes  out  of  the  Psoas  magnus  muscle  a  little  below 
the  hypogastric,  and  thin  crosses  the  Quadratus  Iumborum  to  pass  behind  the 
large  intestine,  after  which  it  crosses  the  inner  lip  of  the  crest  of  the  ilium  pos- 
teriorly. It  now  takes  a  forward  course  on  the  upper  part  of  the  Iliacus  muscle 
to  pierce  the  Transversalis  muscle  near  the  anterior  part  of  the  crest  of  the  ilium 
where  it  communicates  with  the  hypogastric  branch  of  the  ilio-hypogastric 
nerve.  It  pass<  s  through  the  inguinal  canal  and  gives  a  branch  to  the  sper- 
matic cord,  and  to  the  skin  of  the  upper  and  middle  part  of  the  thigh  and  to 
the  scrotum  and  penis  in  the  male,  or  to  the  mons  veneris  and  the  major  lip  in 
1 1n'   female. 

The  second  nerve  of  the  lumbar  plexus  is  the  genito-crural,  which  conies 
from  the  firsl  and  second  lumbar  nerves,  mostly  from  the  second.  It  passes 
through  the  Psoas  magnus  muscle  coming  out  on  the  anterior  surface  of  this 
muscle  at  the  level  of  the  lower  border  of  the  third  lumbar  vertebra.  It  now 
passes  downward  on  the  outer  side  of  the  abdominal  aorta  and  the  common 
iliac  artery,  then  behind  the  meter  where  it  divides  into  an  external  or  genital 
branch  and  an  internal  or  crural  branch.  The  EXTERNAL  or  GENITAL  BRANCH 
gives  a  branch  to  the  external  iliac  artery  ami  it  turns  round  the  deep  epigas- 
tric artery  at  Poupart's  ligament.  It  now  enters  the  inguinal  canal  with  the 
spermatic  cord  in  the  male  or  the  round  ligament  in  the  female.     The  Cremas- 


PLATE  LXXIX. 


PtANTARIS 


OUTER  HEAD  OF  GASTROCNEMIUS 


BICEPS 


ANTERIOR  TIBIAL  ARTERY 


INNER  HEAD    OF  GASTROCNEMIUS 


i TENDON  OF  SEMIMEMBRANOSUS 


PERONEUS       BREVIS 


TIBIALIS 
POSTICUS. 


POSTERIOR  TIBIAL      NERVE 
POSTERIOR    TIBIAL     ARTERY 


TENOO     ACHILLIS 


Muscles  of  Back  of  Leg  (Deel  Layer). 
209 


210  ANATOMY    IN    A    NUTSHELL. 

tciic  muscle  is  supplied  by  this  nerve,  it  also  sends  branches  to  the  integument 
of  the  scrotum  in  the  male  or  the  major  lip  in  the  female.  The  internal  or 
crural  branch  passes  beneath  Poupart's  ligament  on  the  outer  side  of  the 
femoral  artery.  It  pierces  the  fascia  lata  to  supply  the  integument  in  the 
middle  of  the  upper  third  of  the  thigh. 

The  third  nerve  of  the  lumbar  plexus  is  the  external  cutaneous,  which 
conies  from  the  second  and  third  lumbar  nerves.  After  passing  from  the  outer 
border  of  the  Psoas  magiius  muscle  it  crosses  the  Iliacus  muscle,  prior  to  this 
it  pa>ses  behind  the  caecum  on  the  right  side  and  the  iliac  colon  on  the  left. 
Below  the  anterior  superior  spine  of  the  ilium  it  passes  under  Poupart's  liga 
iniiii  in  the  outer  border  of  Scarpa's  triangle.  It  now  crosses  in  front  of  the 
Sartorius  muscle  where  it  divides  into  two  branches,  an  anterior  and  a  posterior 
brunch.  Tin:  anterior  BRANCH,  after  passing  in  the  deep  fascia  for  about 
four  inches,  becomes  cutaneous,  and  most  always  divides  into  an  external 
branch  which  supplies  the  skin  of  the  lower  half  of  the  outer  side  of  the  thigh. 
and  an  internal  branch  which  is  distributed  to  the  skin  of  the  outer  side  of  the 
front  of  the  thigh  as  far  as  the  knee.  The  posterior  branch  supplies  the  in- 
tegument of  the  outer  side  of  the  thigh  from  the  greater  trochanter  to  the  middle 
of  the  thigh. 

The  patellar  plexus  is  formed  by  branches  from  the  long  saphenous  and 
internal  cutaneous  and  middle  cutaneous,  and  external  cutaneous. 


LESSON  LVII. 
Tlu  fourth  nerve  of  the  lumbar  plexus  is  the  anterior  crural,  which  is  the 
largesl  n<  rve  of  this  plexus.  It  comes  from  the  anterior  branches  of  the  sec- 
ond, third,  and  fourth  nerve,  and  after  passing  through  the  outer  border  of  the 
Psoas  magnus  muscle,  it  passes  tinder  Poupart's  ligament  in  a  groove  between 
the  Psoas  magnus  and  Iliacus  muscle  into  Scarpa's  triangle.  In  this  triangle 
it  lit  s  io  the  outer  side  of  the  femora!  artery  from  which  it  is  separated  by  part 
of  the  P>o;i>  magnus.  Hue  it  divides  into  superficial  and  deep  branches,  be- 
twi  i  n  which  pass<  s  die  external  circumflex  artery.  The  superficial  branches 
supply  the  Pectineus  and  Sartorius  muscle  and  give  off  two  cutaneous  branches, 
middle  and  internal.  The  deep  branches  supply  the  Iliacus.  the  Rectus 
femoris,  Vastus  interims.  Vastus  externus,  Crueus  and  Subcrureus  muscle,  and 
gives  off  the  internal  or  long  saphenous  nerve  which  is  cutaneous.  This  an- 
terior crural  nerve  passes  to  eight  muscles,  all  the  muscles  on  the  front  of  the 
leg  except  tin  Tensor  fascia  femoris,  and  in  its  place  it  supplies  the  Iliacus  of 
the  deep  abdominal  region.  It  supplies  the  Pectineus  of  the  internal  femoral 
region.  The  nerve  to  the  Pectineus  passes  behind  the  femoral  sheath  and  in 
fiont  of  the  Psoas  magnus  to  end  in  the  anterior  surface  of  the  Pectineus.  The 
nerve  to   the  Sartorius  ends  in   the  upper  part   of  the  muscle.     The  middle 

<  utaneoi  -  \i  u\  i;  divides  into  two  branches,  the  outer  one  of  which  pierces  the 
Sartorius  and  it  together  with  the  inner  branch  becomes  cutaneous  at  the  upper 
third  of  the  thigh,  and  the  two  pass  down  as  far  as  the  knee-joint  where  they 

<  nt(  r  into  the  patellar  plexus.  Tin;  internal  cutaneous  branch  divides  into 
an  ai  i  d  post<  rior  division  and  supplies  integument  on  the  inner  side  of 


PLATE  LXXX. 


THORACIC 


MUSCULOCUTANEOUS 


INTERNAL  CALCANEAN 


SHORT     SAPHENOUS 
EXTERNAL     PLANTAR 
S    IHUSLULUCUIANbOUS 

ANTERIOR     TIBIAL 


internal  plantar 

Cutaneous  Nerve  Supply  of  the  Lowkf.  Extremity 

211 


212  ANATOMY    IN    A    NUTSHELL. 

the  thigh  from  the  middle  of  the  thigh  to  the  knee.  The  posterior  one  of  these 
branches  helps  to  form  the  subsartorial  plexus  which  lies  on  the  roof  of  Hunter's 
canal.  The  other  nerves  in  the  subsartorial  plexus  are  the  long  saphenous, 
and  branches  from  the  obturator. 

The  muscular  branch  which  passes  to  the  Rectus  muscle  sends  an  articu- 
lar branch  to  the  hip-joint,  while  the  muscular  branch  to  the  Vastus  internus 
sends  an  articular  branch  to  the  knee-joint.  The  long  saphenous  nerve  sends 
an  articular  branch  to  the  ankle-joint. 

The  blood  supply  of  the  lumbar  plexus  comes  from  the  ilio-lumbar  arteries. 

The  obturator  nerve  is  derived  from  the  second,  third  and  fourth  sacral 
nerves.  Its  largest  root  is  from  the  third  nerve.  After  it  passes  from  the  sub- 
si  ance  of  the  inner  border  of  the  Psoas  magnus  muscle  at  the  posterior  part  of 
the  brim  of  the  pelvis,  the  ilio-lumbar  artery  separates  it  from  the  lumbo-sacral 
cord.  It  now  crosses  the  internal  iliac  vessels  and  the  ureter,  passing  in  the 
extraperitoneal  fat  below  the  obliterated  umbilical  (hypogastric)  artery,  along 
the  inner  surface  and  upper  part  of  the  Obturator  internus  muscle.  It  now 
passes  through  the  obturator  foramen  above  the  obturator  membrane.  In  the 
pelvis  it  lies  above  the  obturator  artery.  After  passing  out  of  the  pelvis  it 
divides  into  two  branches,  an  anterior  and  a  posterior  division.  The  anterior 
division  crosses  the  Obturator  externus  muscle  and  passes  between  the  Pectineus 
and  Adductor  brevis.  It  sends  (1)  an  articular  branch  to  the  hip-joint.  (2)  a 
branch  to  the  femoral  artery,  which  is  an  example  of  the  gray  rami.  (3)  Cutane- 
ous branch  to  the  subsartorial  plexus.  (4)  muscular  branches  to  the  Adductor 
longus,  Adductor  brevis,  the  Gracilis  and  the  Pectineus  muscle.  The  pos- 
terior division  passes  between  the  Adductor  brevis  and  Adductor  magnus 
after  piercing  the  upper  part  of  the  Obturator  externus.  It  gives  off  (a)  muscu- 
lar 1 'ranches  to  the  Obturator  externus  and  Adductor  magnus,  and  (b)  articu- 
lar branches  to  the  hip-joint  and  knee-joint. 

Obturator  accessory  nerve,  which  is  present  in  a  little  more  than  one-fourth 
of  the  cases,  comes  from  the  second  and  third  lumbar  nerves.  It  passes  along 
the  inner  border  of  the  Psoas  muscle  between  the  roots  of  the  anterior  crural 
and  obturator  nerves.  It  does  not  pass  through  the  obturator  foramen,  but 
passes  in  front  of  the  brim  of  the  pelvis  beneath  the  Pectineus  muscle.  Its 
branches  are  (1)  a  communicating  branch  to  the  obturator  nerve.  (2)  an  artic- 
ular branch  to  the  hip-joint,  and  (3)   a  muscular  branch  to  the  Pectineus. 


LESSON  LVI1I. 
Sacral  Plexus.     (Plates  LXIII-LXXIII.) 

The  sacral  plexus  is  formed  by  the  lumbo-sacral  cord  and  the  anterior 
branches  of  the  first,  second,  third,  and  a  part  of  the  fourth  sacral  nerves. 

Tin-  lumbi  -sacral  cord  is  formed  by  a  part  of  the  fourth  lumbar  nerve  and 
all  i  f  the  fifth  lumbar  nerve. 

This  plexus  is  situated  <  n  the  anterior  surface  of  the  Piriformis  muscle 
and  behind  the  pelvic  fascia  and  the  branches  of  the  internal  iliac  artery.  It 
gives  >>^  (A)  viscera]  branches,  (B)  muscular.  (C)  cutaneous,  (D)  terminal 
branches.  (E)  Greal  sciatic  and  its  branches. 


ANATOMY    IN    A    NUTSHELL. 


213 


Under  (A)  visceral  branches,  we  have  branches  to  the  pelvic  viscera  from 
the  second,  third,  and  fourth  sacral  nerves.  Under  (B)  muscular  branches. 
(1)  The  nerve  to  the  Pyriformis  comes  from  the  first  and  second  sacral  nerves. 
This  nerve  leaves  the  pelvis  through  the  great  sacro-sciatic  foramen,  and  after 
crossing  the  spine  of  the  ischium  enters  the  Pyriformis  muscle  on  its  internal 
surface. 


PLATE  LXXX1. 


Cutaneous  Nerve  Supply  of  the  Plantab  Surface  of  the  Foot. 

(2)  The  superior  gluteal  nerve  is  derived  from  the  fourth  and  fifth 
lumbar  and  first  sacral  nerve.  It  leaves  the  pelvis  above  the  Pyriformis  muscle 
with  the  gluteal  vessles.     It  supplies  the  Gluteus  medius,  Gluteus  minimus  and 

Tensor  fascia  femoris.     It  also  sends  sympathetic  branches,  which  are    gray 
rami,  to  the  bone,  ligament,  fascia,  and  vessels  -  see  sympathetic  nerve. 


214  ANATOMY    IN    A    NUTSHELL. 

(3)  The  inferior  gluteal  nerve  is  derived  from  the  fifth  lumbar,  first 
and  second  sacral  nerves.  It  leaves  the  pelvis  below  the  Pyriformis  muscle 
with  the  sciatic  and  pudic  vessels  and  nerves.  It  gives  muscular  branches  to 
the  ( Huteus  maximus. 

(4)  The  nerve  to  the  Quadratus  femoris  is  derived  from  the  fourth,  fifth 
lumbar,  and  first  sacral  nerves.  It  leaves  the  pelvis  below  the  Pyriformis 
muscle.  It  sends  a  branch  to  the  Gemellus  inferior,  and  also  one  to  the  hip- 
joint. 

i.")i  The  nerve  i<»  the  Obturator  interims  is  derived  from  the  fifth  lumbar, 
tirst  and  second  sacral  nerves.  It  leaves  the  pelvis  below  the  Pyriformis  mus- 
cle and  re-enters  the  pelvis  through  the  lesser  sacrc -sciatic  foramen  to  be  dis- 
tributed  to  the  inner  surface  of  this  muscle.  It  gives  a  branch  to  the  Gemellus 
superior. 

Under  ((')  cutaneous  branches  we  have,  (Plate  LXXYIII.) 

(1)  The  small  sciatic  is  derived  from  the  first,  second,  and  third  sacral 
nerves.  It  leaves  the  pelvis  through  the  great  sacro-sciatic  foramen  below  the 
Pyriformis  muscle  with  the  sciatic  vessels  and  the  great  sciatic  nerve,  inferior 
gluteal  nerve,  internal  pudic  nerve  and  vessels.  At  the  lower  border  of  the 
Glutens  maximus  it  passes  behind  the  long  head  of  the  Biceps  and  descends 
beneath  the  deep  fascia  to  the  popliteal  space.  Some  say  it  supplies  the  Gluteus 
maximus,  bu1  outside  of  supplying  this  one  muscle  it  is  cutaneous.  Its  branches 
are  first;  peroneal  cutaneous  which  supplies  the  skin  of  the  upper,  inner,  and 
posterior  aspects  of  the  thigh  and  perineum.  One  of  these  branches,  the  in- 
ferior or  long  pudendal  nerve,  crosses  the  tuberosity  of  the  ischium  and  per- 
forates the  fascia  lata  and  Colles'  fascia  to  enter  the  anterior  compartment  of 
the  perineum.  In  the  perineum  it  communicates  with  the  superficial  perineal 
nerves  and  sends  branches  to  the  skin  of  the  scrotum  in  the  male,  and  to  the 
major  lip  in  the  female.  Second;  Femoral  cutaneous  branch  which  supplies 
the  integumenl  on  the  central,  inner  and  outer  aspects  of  the  posterior  partof 
the  thigh.  Third;  Gluteal  or  ascending  cutaneous  branches  to  supply  the  skin 
over  the  lower  and  outer  part  of  the  Gluteus  maximus. 

(2)  Perforating  cutaneous  nerve  is  derived  from  the  second  and  third  sacral 
nerves.  It  perforates  the  greater  sacro-sciatic  ligament  and  supplies  the  skin 
over  the  lower  and  inner  part  of  the  Gluteus  maximus. 

Under  I  D)  terminal  branches  we  have. 

(1)  The  pudic  nerve  is  derived  from  the  second,  third  and  fourth  sacral 
nerves.  It  haves  the  pelvis  below  the  Pyrifomis  muscle.  It  now  crosses  the 
spine  of  the  ischium,  being  on  the  inner  side  of  the  internal  pudic  artery,  which 
it  accompanies  through  the  lesser  sacro-sciatic  notch  into  Alcock's  canal  where 
it  divides  into  three  branches.  First;  the  inferior  hemorrhoidal  nerve  which 
passes  through  the  inner  wall  of  Alcock's  canal  towards  the  anus  to  supply  the 
sphincter  ani  and  the  adjacent  integument.  Second;  the  perineal  branch 
which  has  a  cutaneous  branch  called  the  superficial  perineal.  It  leaves  Alcock's 
canal  ami  pierces  the  base  of  the  triangular  ligament  and  is  distributed  to  the 
skin  of  the  scrotum  in  the  mule  or  the  major  lip  in  the  female.  Third;  the  dor- 
sal nerve  of  the  penis,  pierces  the  posterior  layer  of  the  triangular  ligament  and 


ANATOMY   IN   A    NUTSHELL. 


215 


passes  through  the  deep  perineal  space  along  the  inner  margin  of  the  ramus  of 
the  pubic  bone.  It  now  pierces  the  anterior  layer  of  the  triangular  ligament, 
Lying  between  the  cms  penis  and  the  pubic  hone,  and  gives  a  vaso-motor  branch 
to  the  corpus  cavernosum,  and  passes  to  the  dorsum  of  the  penis  to  supply  the 
integument,  glans  and  prepuce  in  the  maleor  clitoris  in  the  female.  It  is  called 
the  dorsal  nerve  of  the  clitoris  in  the  female  and  is  much  smaller. 

PLATE  LXXXII. 


CAPSU  LAR  LIGAMENT  DIVIDED 


UUI  SURFACE  OF  CAPSULAR  LIGAMENT 


Ligaments  of  Hip-Joint. 


LESSON  LIX. 

Under  (E)  great  sciatic  nerve  and  its  branches  we  have,  (Plate  LX  Will.) 
(1)  The  great  sciatic  nerve  and  its  branches  which  supply  both  muscles  ami 
integument  below  the  knee-joint  but  muscles  only  above  this  joint.  It  sup- 
plies thirty-seven  muscles  in  all.  It  isthe  largest  nerve  in  the  body  and  is  a  con- 
tinuation of  the  sacral  plexus, except  the  fourth  sacral  nerve, since  thegreal  sciatic 
isformed  by  thelumbo-sacral  cord  and  the  anterior  branches  of  the  first,  second 
and  third  sacral  nerves.  After  passing  out  of  the  pelvis  below  the  Pyriformis 
muscle  it  passes  between  the  great  trochanter  and  the  tuberosity  ^i  the  ischium. 
It  may  perforate  the  Pyriformis  muscle.  It  generally  divides  at  the  lower  one- 
third  of  the  thigh  into  an  external  popliteal  or  peroneal  and  an  internal  popliteal 
or  popliteal  nerve.  This  division  may  take  place  immediately  after  the  nerve 
leaves  the  pelvis.      In  its  course  down  the  hack  of  the  thigh  (Plate  LXXVIII)  it 


216  ANATOMY    IX    A    NUTSHELL. 

lies  upon  the  l>ack  of  the  ischium,  the  nerve  to  Quadratus  femoris.  the  Gemelli 
muscles,  Obturator  interims.  Quadratus  femoris.  and  Adductor  magnus  muscles. 
It  i-  accompanied  by  the  sciatic  artery  and  the  small  sciatic  nerve.  In  the 
tipper  part  of  its  course  it  is  covered  by  the  Gluteus  maximus  and  in  its  lower 
part  by  the  long  head  of  the  Biceps.  Before  it  divides  it  gives,  (a)  articular 
branches  t<>  the  hip-joint  which  perforates  the  capsular  ligament  posteriorly. 
(b)  MUS<  ri. ak  branches  beneath  the  long  head  of  the  Biceps  to  the  Biceps. 
Semitendinosus,  Semimembranosus,  and  Adductor  magnus.  The  fibers  in  the 
internal  popliteal  or  popliteal  are  from  the  fourth  and  fifth  Lumbar,  first,  second. 
ami  third  sacral.  (Plate  LXXVII.)  This  is  the  larger  of  the  two  divisions, 
it  passes  through  the  popliteal  space.  At  the  lower  border  of  the  Popliteus 
muscle  it  is  called  the  posterior  tibial  nerve.  It  is  like  the  median  nerve  of 
arm  in  that  it  lies  at  first  on  the  outer  side  of  the  artery,  then  crosses  it  to  lie 
on  its  inner  side.  It  gives  off  the  following  branches.  (1)  articular  branches 
to  the  knee-joint  which  are  three  in  number:  first,  superior  internal;  second, 
superior  external,  and  third,  azygos. 

(2)  Muscular  branches  to  the  Gastrocnemius.  Plantaris,  Popliteus.  and 
Soleus. 

(3)  Communicans  poplitei  which  joins  the  communicans  peronei  to  form 
the  short  saphenous  nerve,  which  supplies  integument  on  the  posterior  part  of 
the  Leg  and  on  the  outer  side  of  the  foot.  (4)  This  nerve  continues  as  the 
posterior  tibial  after  it  passes  the  lower  border  of  the  Popliteus  muscle.  The 
posterior  tibial  nerve  crosses  the  posterior  tibial  vessels  from  within  out.  just  the 
opposite  from  the  median  and  popliteal  nerves.  (Plate  LXXVIII.)  In  the 
lower  part  of  the  leg  these  posterior  tibial  vessels  and  the  nerve  lie  parallel  with 
the  inner  border  of  the  tendo  Achillis.  The  branches  of  this  nerve  are.  (1)  mus- 
cular to  the  Soleus.  Tibialis  posticus.  Flexor  longus  hallucis.  Flexor  longus 
digitorum.  (2)  Internal  calcanean  (cutaneous)  which  passes  with  the  in- 
ternal calcaneal)  artery.  It  supplies  the  integument  and  fascia  of  the  heel  and 
a  part  of  the  sole.  (3)  Articular  branches  to  the  ankle.  (4)  Internal 
axd  external  plantar  nerves,  which  are  formed  by  the  division  of  the  pos- 
terior tibial  nerve  at  a  point  midway  between  the  internal  malleolus  and  inner 
tubercle  of  the  os  calcis.  These  nerves  accompany  the  internal  and  external 
arteries.  While  the  internal  plantar  nerve  islarger  than  the  external  plantar,  the 
arteries  are  just  the  reverse. the  external  being  Larger  than  the  internal.  The  in- 
ternal nerve  supplies  the  following  five  muscles.  (1)  Abductor  hallucis,  (2)  Flexor 
brevis  digitorum,  (3)  and  (4)  the  two  inner  Lumbricales.  (5)  Flexor  brevis 
hallucis.  It  also  supplies  integument  on  the  inner  aspect  of  the  plantar  sur- 
face of  the  fo«.t.  (Plate  LXXXI.)  The  external  plantar  nerve  supplies  the 
following  fourteen  muscles.  (1)  Abductor  minimi  digiti,  (2)  and  (3)  the  two 
outer  Lumbricales,  (4)  Flexor  accessorius,  (5)  Flexor  brevis  minimi  digiti.  the 
seven    [nterossei  make    twelve.   (13)    the   Adductor   transversus    hallucis.    and 

1  I     the  Adductor  obliquus  hallucis.     This  nerve  also  supplies  integument  on 
the  plantar  surface  of  the  foot. 


ANATOMY    IN  A    NUTSHELL. 


217 


LESSON  LX. 

The  external  popliteal  or  peroneal  nerve  passes  along  the  outer  part  of  the 
popliteal  space  close  to  the  tendon  of  the  Biceps  muscle  as  far  as  the  head  of  the 
fibula.  (Plate  LXXVIII.)  It  is  about  half  as  large  as  the  popliteal  nerve.  It 
gives  (1)  articular  branches  to  the  knee-joint  (superior  and  inferior  ex- 
ternal) also  recurrent  articular  branch  to  the  superior  tibio-fibular  articulation 
(2)  Cutaneous  branches  which  supply  the  integument  along  the  back  part 
and  outer  side  of  the  leg.  (3)  Communicans  peronei  which  joins  the  com- 
municans   poplitei   to   form    the   short   saphenous   nerve.     Museulo-eutaneous 

PLATE  LXXXIIL 


INTERNAL  TUBEROSITY 


EXT  LATERAL  LIGAMENT 


LlG AMENTUM    PATELLA. 

which  begins  on  the  head  of  the  fibula  and  passes  down  between  the  Peronei 
muscles  and  the  Extensor  brevis  digitorum  pierces  the  deep  fascia  a1  the  lower 
one-third  of  the  leg  on  its  front  and  outer  side.  This  nerve  supplies  the  I'er- 
oneus  Longus,  Peroneus  brevis,  and  the  integumenl  mi  the  dorsum  of  the  foot. 

The  INTERNAL  TERMINAL  BRANCH  of  the  nuiselilo-rutaneous  nerve  passes  in 
front  of  the  ankle-joint  and  divides  into  two  branches.  The  inner  branch 
passes  to  the  inner  side  of  the  great  toe  and  sends  twigs  to  the  integumenl  on 
the  inner  side  of  the  foot.     The  outer  branch  passes  to  the  base  of  the  cleft 


218  ANATOMY    IX    A    NUTSHELL. 

between  the  second  and  third  toes  and  divides  to  supply  the  adjacent  sides  of 
the  cleft. 

The  external  terminal  branch  is  the  smaller  of  the  two  and  passes  along 
the  outer  side  of  the  dorsum  of  the  toot  and  divides  into  two  branches.  The 
inner  one  suppli*  s  t  he  integument  of  the  adjacent  sides  of  the  third  and  fourth 
toes.  The  outer  one  supplies  the  integument  on  the  adjacent  sides  of  the  fourth 
and  fifth  toes.  The  outer  side  of  the  fifth  toe  receives  the  short  saphenous 
nerve. 

The  anterior  tibial  nerve  comes  from  the  end  of  the  peroneal  nerve  just 
internal  to  the  musculo-cutaneous  between  the  Peroneus  longus  and  the  neck 
of  the  fibula.  It  passe-  forward  and  inward  beneath  the  Extensor  longus  dig- 
itorum  to  lie  in  the  interval  between  this  muscle  and  the  Tibialis  anticus.  It 
descends  on  the  interosseous  membrane  with  the  anterior  tibial  artery  to  the 
front  of  the  ankle-joinl  where  it  divides  into  an  inner  and  an  outer  terminal 
branch.  The  inner  terminal  branch  passes  down  along  the  dorsalis  pedis  artery 
and  supplies  the  integument  along  the  adjacent  sides  of  the  first  and  second 
toes.  It  also  supplies  the  periosteum  of  the  adjacent  bones,  the  metatarso- 
phalangeal and  inter-phalangeal  joints.  It  helps  to  supply  the  First  dorsal 
interosseous  muscle.  The  outer  terminal  branch  passes  under  the  Extensor 
brevis  digitorum  outward.  This  branch  has  a  ganglion  upon  it  which  supplies 
the  Extensor  brevis  digitorum,  tarsal  joints  and  the  bones,  periosteum,  and 
joints  of  the  three  outer  intermetatarsal  spaces.  It  helps  to  supply  the  Second 
dorsal  interosseous  muscle. 

The  anterior  tibial  nerve  gives  ( 1 )  muscular  branches  to  Tibialis  anticus. 
Extensor  longus  digitorum,  Extensor  proprius  hallucis,  Peroneus  tertius,  Ex- 
tensor brevis  digitorum,  and  as  said  before  helps  to  supply  two  inner  Dorsal 
interossei.  (2)  Articular  branches  to  the  inferior  tibio-fibular  articulation 
and  the  ankle-joint.      (Plate  LXXY1.) 

The  coccygeal  plexus  (Plate  LXIII-LXXIII.)  is  formed  by  the  anterior 
branches  of  part  of  the  fourth  sacral  nerve,  the  fifth  sacral  and  the  coccygeal 
nerve.  It  is  situated  on  the  inner  surface  of  the  Coccygeus  muscle  and  behind 
the  Second  portion  of  the  rectum.  Its  muscular  branches  supply  the  Coccygeus 
muscle  and  Levator  aid.  while  its  visceral  branches  together  with  the  sympa- 
thetic supply  the  pelvis  viscera.  For  the  complete  distribution  of  the  cutan- 
eous nerve  supply  of  the  lower  limb  see  (Plates  LXXX-LXXXI.) 

LESSOX  LXI. 
Thk  Superficial  Fascia  of  the  Thigh. 
The  superficial  fascia  i>  continuous  with  that  of  the  leg  below  and  that  of 
the  abdomen  above.  It  has  an  superficial  and  a  deep  layer,  between  which 
layers  are  die  superficial  vessels  and  nerves.  Really  these  structures  are  in 
the  deep  layer  but  the  line  of  distinction  cannot  be  closely  drawn  between  the 
superficial  deep  layers.  This  fascia  is  beneath  1  he  integument  and  forms  an 
investment  for  the  entire  thigh.  It  is  attached  (1)  to  the  margin  of  the  saph- 
enous opening,  (2)  to  the  femoral  sheath  through  the  saphenous  opening,  (3) 
to  the  fascia  lata  below  Poupart's  ligament.  The  cribriform  fascia,  which 
form-  one  of  the  coverings  of  ;)  femoral  hernia,  is  that  part  of  the  superficial 


ANATOMY    IX    A     NUTSHELL. 


219 


fascia  which  covers  the  saphenous  opening.  This  fascia  is  perforated  by  the 
long  saphenous  vein  and  a  number  <>f  vessels.  The  superficial  fascia  has  a  very 
intimate  attachment  to  the  deep  fascia  below  Poupart's  Ligament,  thus  in  ex- 
travasation of  urine,  it  cannot  pass  down  into  the  superficial  fascia  of  the  thigh. 


PLATK  LXXXIV 


PLANTARIS 

OUTER  HEAD  OF 
GASTROCNEMIUS 


TENDON    OF    POPLITEUSv    A      •  '  \     . 

EXTERNAL  LATE 
LIGAMENTS 

-     .;:.*7V- 


TENDON  OF  ADDUCTOR  MAGN05 


TENDON  OF  BICEPS 


"al    m\  '  Q  *^^^  fl 

f4 


NNER  HEAD  OF  GASTROCNEMIUS 


~~TEf;20'J  OF  SEMI-MEWSRANOSUS  WITH  ITS 

SLIP    TD    THICKENED    THE    POSTERIOR    LIGAMENT 


/HEAD  P 


mi  '    ' 

TIBIOFIBULAR  LIGAMENT^         ,',|    \\\  }      T'B'A         ■ 


POSTERIOR  SUPERIOR 


INTEROSSEOUS 
MEMBRNE 

Posterior  Ligament  of  Knee-Joint. 

Deep  Fascia  of  the  Thigh. 

The  deep  fascia  of  the  thigh  is  called  fascia  lata,  and  form-  a  strong  cover- 
ing lor  the  thigh  beneath  the  skin  and  superficial  fascia.  It  is  thick  in  front 
and  externally,  but  thin  behind  and  internally.  The  Gluteus  maximus,  the 
Tensor  fascia  femoris,  the  Biceps,  the  Sartorius,  and  Quadriceps  extensor  mus- 
cles give  expansions  to  the  fascia  lata.  The  fascia  lata  is  attached  to  Poupart's 
ligament  and  the  body  of  the  pubic  bone  anteriorly,  to  the  tuberosity  of  the 
ischium  and  the  rami  of  the  pubes  and  ischium  internally,  to  the  back  of  the 
sacrum  and  coccyx  posteriorly,  to  the  head  of  the  fibula,  tuberosities  of  the 
tibia,  and  condyles  of  the  femur  distally.     The  external  Intermuscular  septum 


220  ANATOMY    IN    A    NUTSHELL. 

is  attached  to  the  linea  aspera  and  extends  from  the  insertion  of  the  Gluteus 
maximus  to  the  outer  condyle  of  the  femur.  It  separates  the  Vastus  externus 
from  the  short  head  of  the  Biceps  and  gives  attachment  to  both  of  these  mus- 
cles. The  internal  intermuscular  septum  is  attached  to  the  linea  aspera  and 
extends  from  the  lesser  trochanter  to  the  adductor  tubercle,  thus  separating 
the  Vastus  in  tenuis  from  the  Pectineus  and  Adductors.  This  intermuscular 
septum  is  perforated  by  branches  of  the  profunda  artery  which  pass  to  the 
hamstring  muscles  and  by  the  superficial  femoral  artery  which  passes  into  the 
popliteal  space  through  an  opening  in  the  Adductor  magnus.  Smaller  septa 
are  given  off  from  the  fascia  lata  to  ensheath  each  muscle. 

The  ilio-tibial  band  (Plate  LXXIV.)  is  a  special  part  of  the  fascia  lata 
which  passes  from  the  front  part  of  the  crest  of  the  ilium  down  the  thigh  as  two 
layers,  one  superficial  to  and  the  other  beneath  the  Tensor  fascia  femoris,  at 
the  lower  end  of  which  muscle  these  two  layers  become  blended  and  having 
received  the  insertion  of  this  muscle  it  passes  down  to  be  inserted  into  the  ex- 
ternal tuberosity  of  the  tibia.  Another  special  portion  of  the  fascia  lata  is 
called  the  gluteal  aponeurosis  and  takes  its  origin  from  the  outer  lip  of  the  crest 
of  the  ilium  posterior  to  the  ilio-tibial  band.  This  fascia  covers  the  Gluteus 
medius  muscle  and  divides  at  the  anterior  border  of  the  Gluteus  maximus  to 
enclose  it.  The  iliac  portion  of  the  fascia  lata  is  behind  the  femoral  vessels  but 
in  front  of  the  pubic  portion.  This  portion  is  attached  to  the  crest  of  the  ilium 
and  to  the  whole  length  of  Poupart's  ligament  and  to  the  ilio-pectineal  line  with 
Gimbernat's  ligament  where  ^continuous  with  the  iliac  fascia.  The  pubic  por- 
tion of  the  fascia  is  attached  above  to  the  ilio-pectineal  line.  It  passes  beneath 
the  femoral  vessels  to  which  it  is  attached  and  crosses  the  Gracilis,  Adductor 
longus  and  Pectineus  muscles.  The  saphenous  opening  is  between  the  iliac 
and  pubic  portions  of  the  fascia  lata  and  leads  from  the  space  of  the  superficial 
fascia  to  the  femoral  vessels.  It  is  an  oval  shaped  aperature  which  is  about  an 
inch  and  a  half  in  length  and  half  an  inch  in  width.  It  is  directed  obliquely 
downward  and  outward  at  the  upper  and  inner  part  of  the  thigh  just  below 
Poupart's  ligament.  The  inner  boundary  of  the  opening  is  posterior  to  the 
outer  margin  and  behind  the  femoral  vessels.  It  is  through  the  saphenous 
opening  that  a  femoral  hernia  passes  after  descending  along  the  crural  canal. 
The  outer  margin  of  this  opening  forms  the  falciform  process  which  passes  in 
fronl  of  the  femoral  vessels  and  is  attached  to  Poupart's  ligament  and  the  spine 
of  the  os  pubes  and  the  pectineal  line  where  it  is  continuous  with  the  pubic 
portion. 

LESSON  LXII. 
The  Fascia  of  the  Leg. 
The  superficial  fascia  of  the  leg  is  continuous  with  that  of  the  thigh  and 
beneath  it  i-  the  deep  fascia  of  the  leg,  which  forms  an  investment  for  the  mus- 
cles but  is  not  continued  over  the  subcutaneous  surfaces  of  the  bone.  Above 
it  joins  the  fascia  lata  and  receives  an  expansion  from  the  tendon  of  the  Biceps 
externally  and  from  the  tendons  of  the  Sartorius,  Gracilis,  Semitendinosus  in- 
ternally. Anteriorly  it  blends  with  the  periosteum  covering  the  subcutaneous 
surface  of  the  tibia  and  with  that  covering  the  head  and  the  external  malleolus 


AXATOMY    IX    A    XUTSHELL. 


221 


of  the  fibula.  Below  it  is  continuous  with  the  anterior  annular  ligament  of  the 
ankle.  It  is  thin  where  it  covers  the  Gastrocnemius  and  Soleus  but  thick  and 
dense  in  the  upper  and  anterior  part  of  the  leg  where  it  gives  attachment  to  the 
Tibialis  amicus  and  Extensor  longus  digitorum.  At  the  lower  part  of  the  pop- 
liteal space  it  is  strengthened  by  transverse  fibers  and  is  perforated  by  the 
short  saphenous  vein. 

The  deep  fascia  of  the  leg  gives  off  several  small  septa  which  enclose  each 
muscle  and  externally  it  gives  off  two  strong  intermuscular  septa  which  enclose 

PLATE  LXXXV. 


APERTURE  LEADING  INTO  THE    BURSA    BENEATH    THE 
QUADRICEPS  EXTENSOR. 


ATTACHMENT  OF  CAPSULAR.  OR 

'  ANTERIOR    LIGAMENT    TO 

FEMUR 


ANTERIOR  CRUCIAL- 
LIGAMENT 


INTERNAL    SEMILUNAR 
INTERNAL    LATERAL 
LIGAMENT 


POSTERIOR  CRUCIAL 
LIGAMENT 

EXTERNAL  LATERAL 
LIGAMENT 

EXTERNAL    SEMILUNAR 


TRANSVERSE      LIGAMENT 


Showing  Condyles  and  Ligaments  of  Knee-Joint — Anterior  View. 

the  peronei  muscles,  thus  separating  them  from  the  muscles  on  the  anterior 
tibial  region  and  the  muscles  on  the  posterior  tibial  region.  It  also  gives  off  a 
deep  transverse  fascia  of  the  leg  which  passes  between  the  superficial  and  deep 
muscles  in  the  posterior  tibio-fibular  region. 

The  anterior  annular  ligament  (Plate  LXXV.)  consists  of  two  portions,  a 
superior  or  a  vertical  portion,  and  an  inferior  or  horizontal  portion.  The 
superior  portion  passes  across  the  front  of  the  leg  between  the  anterior  borders 


222 


ANATOMY    IN    A    XITSHELL. 


of  the  tibia  and  the  fibula  just  above  the  malleoli  and  binds  down  the  extensor 
tendons  as  they  descend  on  the  front  of  the  tibia  and  fibula.  The  inferior 
portion  begins  on  the  outer  side  of  the  calcaneum  and  divides  into  two  layers 
at  the  outer  border  of  the  Peroneus  tertius,  one  passing  in  front,  the  other  be- 
hind ami  at  the  inner  border  of  the  Extensor  longus  digitorum  these  layers 
mute  thus  forming  a  canal  through  which  these  muscles  pass.  This  inferior 
portion  of  the  anterior  annular  ligament  now  divides  into  two  branches  one  of 
which  passes  upward  to  be  inserted  in  the  front  of  the  internal  malleolus  and 
the  other  passes  across  to  be  inserted  on  the  scaphoid  and  internal  cuneiform 
bon<  s  and  the  plantar  fascia.     The  tendon  of  the  Tibialis  anticus  has  a  synovial 

PLATE   LXXXYI 


EXPANSION  FROM  QUADRICEPS  EXTENSOR  TENDON 


ANTERIOR  CRUCIAL 


POSTERIOR      CRUCIAL  LIGAMENT 


EXTERNAL  LATERAL  LIGAMENT 


Semilunab    Fibro-Cartjlage  of  Knee-Joint. 

-heath  in  the  superior  portion  of  the  anterior  annular  ligament  and  also  one  in 
the  upper  limb  of  the  inferior  portion,  but  is  passes  under  the  lower  limb  of 
the  inferior  portion. 

|  The  external  annular  Ligament  runs  from  the  extremity  of  the  outer  malleo- 
lus to  the  outer  side  of  the  os  calcis  binding  down  the  Peroneus  longus  and 
Peroneus  brevis,  which  are  enclosed  in  a  single  synovial  membrane. 

The  internal  annular  Ligament  (Plate  LXIX.)  passes  from  the  internal 
malleolus  to  the  internal  margin  of  the  os  calcis.  It  thus  makes  the  grooves 
over  which  it  passes  into  canals  for  the  passage  of  the  tendons  of  the  flexor 
muscles  and  vessels  into  the  sole  of  the  foot.  It  joins  the  deep  fascia  of  the  leg 
above  and  the  plantar  fascia  below  at  the  origin  of  the  Abductor  hallucis.  It 
has  three  canals  which  from  within  outward  transmit  (1)  the  Tibialis  posticus, 
■  udon  of  the  Flexor  longus  digitorum,  then  the  posterior  tibial  vessels 
and  nerve,  (3)  the  tendon  of  the  Flexor  longus  hallucis.  Each  of  these  canals 
is  lined  by  synovial  m<  mbrane. 


ANATOMY    IX    A    NUTSHELL. 


223 


The  fascia  on  the  sole  of  the  foot  is  called  the  plantar  fascia  (Plate  LV.) 
and  is  the  densest  of  all  the  fibrous  membranes.  It  is  divided  into  three  por- 
tions. (1)  A  central  portion  which  is  attached  to  the  inner  tuberosity  of  the  OS 
calcis  and  runs  forward  below  the  Flexor  brevis  digitorum  and  ends  in  front  in 
a  process  for  each  toe  and  in  slips  for  the  skin.  At  its  sides  it  joins  the  lateral 
portions  which  extends  around  the  margins  of  the  foot.  At  the  junction  of  the 
central  with  the  two  lateral  portions  expansions  pass  upward.     (2)  The  ex- 


PLATE  LXXXVII. 


ANTERIOR     LIGAMENT      OF    ANKLE 
CALCANEO-  SCAPHOID-  LIGAMENT 
DORSAL    SCAPHO-CUBOID-  LIGAMENTS 
DORSAL     SCAPHO-CUNEIFORM      LIGAMENTS 
DORSAL    INTER  CUNEIFORM-LIGAMENTS. 
DORSAL   CUBO-CUNEIFORM   LIGAMENT 
DORSAL  TARSO-  METATARSAL  LIGAMENTS 
DORSAL  INTER  METATARSAL   LIGAMENTS 


ANT     INF     IIBin- FIBULAR   LIGAMENT. 
POST  INF  TIBIOFIBULAR    LIGAMENT. 


ANTERIOR    FASCICULUS    OF 
EXTERNAL  LATERAL    LIGAMENT 

POST.  LIGAMENT  OF  ANKLE  JOINT 
*   WV 
EXT.  LATERAL  LIGAMENT 

(POST.  FASCICULUS) 

TENDO  ACHILLIS 


INTERNAL     CALCANEOCUBOID   LIGAMENT 
DORSAL     CALCANEOCUBOID      LIGAMENT 

INFERIOR     CALCANEO-  CUBOID    LIGAMENT 

EXTERNAL  CALCANEO- CUBOID   LIGAMENT 


MIDDLE    FASCICULUS    OF 
EXTERNAL   LATERAL  LIGAMENT 
ANTERIOR   CALCANEO-ASTRAGALOID  LIGAMENT 
INTEROSSEOUS  CALCANEO-ASTRAGALOID  LIGAMENT 
EXTERNAL    CALCANEO-AS TRAGALOIU   LIGAMENT 


Ligaments  of  Ankle — External  View. 


tenia]  portion  which  is  thin  in  front  and  thick  behind  extends  from  the  os  calcis 
io  the  base  of  the  fifth  metacarpal  hone.  It  coversthe  nude'- surface  ofthe  Ab- 
ductor minimi  digiti.  It  is  continuous  with  the  fascia  on  the  hack  of  the  fool 
and  with  the  central  portion  of  the  plantar  fascia.  (3)  The  internal  lateral 
portion  covers  the  Abductor  hallucis  muscle  and  is  quite  thin.  Posteriorly  it 
is  attached  to  the  internal  annular  ligamenl  and  continues  around  the  side  of  the 
foot  with  the  dorsal  fascia,  and  e\l<  rnally  with  the  middle  portion  of  the  plantar 
fascia. 


224 


ANATOMY    IX    A     NUTSHELL. 


REVIEW  QUESTIONS. 

1.  How  many  muscles  in  the  Gluteal  region? 

2.  How  many  of  them  are  attached  to  the  great  trochanter? 

3.  Name  the  muscles  in  the  Gluteal  region. 

4.  What  nerves  supplies  the  Gluteus  maximus? 

.">.  What  nerve  supplies  the  Gluteus  minimus  and  medius? 
(').   What  other  muscle  does  this  nerve  supply? 

7.  Nerve  to  the  Quadratus  femoris  comes  from  which  ones? 

8.  What  other  muscle  does  it  supply? 

9.  Nerve  to  Obturator  interims  comes  from  which  ones? 

10.  What  other  muscle  does  it  supply? 

11.  What  ligaments  make  the  greater  and  lesser  Sacro-sciatic  foramina? 

12.  What   muscle  goes  through  the  Greater? 

13.  What  goes  through  above  the  Pyriformis  muscle? 


OS  CALCIS 


PLATE  LXXXV1II. 

DORSAL   ASTRAGALO- SCAPHOID  LIGAMENT 

DORSAL  AND  INT.  LATERAL   SCAPH0-CUNEIF0RM   LIGAMENTS 
DORSAL   INTERCUNEIFORM    LIGAMENTS 

DORSAL  AND    INT.  LATERAL    TARSO- 
METATARSAL      LIGAMENT 

DORSAL  AND  INT.   LATERAL  METATARSO- 
PHALANGEAL   LIGAMENTS 


DORSAL   AND    INTERNAL 
LATERAL    INTER  PHALANGEAL 
LIGAMENTS 


TIBIO-ASTRAGALOID 
INF.CALCANEO-  LIGAMENT 

scaphoid  ligament 
Ligaments  of  Ankle — Internal  View. 

1  1.   Wha1  ]>:i>ses  through  below  the  Pyriformis  muscle? 

15.  What  muscle  passes  through  the  lesser  Sacro-sciatic  foramen? 

16.  The  Obturator  interims  is  supplied  from  what  plexus? 

17.  The  5th  lumbal-  nerve  belongs  to  what  plexus? 

18.  The  Obturator  externus  is  supplied  from  what  plexus? 

19.  How  many  muscles  are  attached  to  the  Ischium? 

20.  How  many  muscles  are  attached  to  the  Ilium? 

21.  How  many  muscles  are  attached  to  the  Os  Pubis? 

22.  How  many  bones  in  the  pelvis? 
•_':;.   Name   them. 

24.  Name  the  divisions  of  the  Innominate. 

_'.">.  What  bones  form  the  acetabulum? 

26.  Name  the  ligaments  of  the  hip-joint. 

27.  How  many  muscles  are  attached  to  the  femur? 


ANATOMY    IN   A    NUTSHELL.  225 

28.  What  nerve  supplies  the  muscles  in  the  anterior  femoral  region? 

29.  What  nerve  supples  the  muscles  in  the  internal  femoral  region? 

30.  What  nerve  supplies  the  muscles  in  the  posterior  femoral  region? 

31.  The  anterior  crural  and  obturator  nerves  come  from  what  plexus? 

32.  All  the  muscles  on  the  posterior  part  of  femur  and  from  knee  down  are 
supplied  by  what  nerve  and  its  branches? 

33.  How  many  muscles  are  there  from  the  knee  to  the  ankle? 

34.  How  many  on  the  anterior  tibio-fibular  region? 

35.  How  many  in  the  outer  fibular  region? 

36.  How  many  in  the  posterior  region? 

37.  How  many  layers  in  the  posterior  region? 

38.  What  separates  these  two  layers? 

39.  Name  the  seven  muscles. 

40.  Name  the  deep  layer. 

41.  Give  nerve  supply. 

42.  Name  those  in  superficial  layer. 

43.  Give  nerve  supply. 

44.  Which  muscles  are  attached  to  the  tibia  and  fibula? 

45.  What  long  bone  has  the  insertion  of  only  one  muscle? 

46.  What  is  that  muscle? 

47.  Name  the  outer  hamstring. 

48.  Name  the  inner  hamstring. 

49.  Bound  Scarpa's  triangle. 

50.  Who  was  Scarpa? 

Italian  Anatomist.     1747-1832.     He  was  physician  to  Napoleon. 

51.  Give  the  floor  of  Scarpa's  triangle  from  without  inward. 

52.  What  structure  passes  through  the  center  of  this  triangle? 

53.  How  long  is  the  common  femoral  artery? 

54.  It  gives  off  what  branch? 

55.  Passes  through  what  canal? 

56.  Then  through  what  space? 

57.  Then  gives  off  what  branches? 

58.  Where  does  this  division  take  place? 

59.  Anterior  tibial  passes  to  the  front  of  the  leg  between  the  two  heads  of 
what  muscle? 

60.  Anterior  tibial  continues  below  the  ankle  as  what  artery? 

61.  The  posterior  tibial  artery  gives  off  what  large  branch? 

(i2.  The  posterior  artery  divides  into  what  as  it   passes    into   the   plantar 
surface  of  the  foot? 

63.  Describe  the  Anterior  annular  Ligament. 

64.  Describe  the  Internal  annular  ligament. 

65.  Describe  the  External  annular  Ligament. 
(if).    Describe  the   Plantar  fascia. 

()7.   Name  the  muscles  the  Great    Sciatic   supplies  on  posterior  part  of  the 

Leg. 
68.   It    divides    into    what    branches? 


PLATE  L XX XIX. 


TALI  PES"" 
CAVUS-OR-ARC^U  A  TUS 


TAL  I  P  E  S 

E~QU  INO-VALG.U'S* 


Forms  of  Cub  Foot. 
220 


ANATOMY    IX    A   NUTSHELL.  227 

69.  The  external  popliteal  nerve  divides  into  what  branches? 

70.  The  anterior  tibial  supplies  what  muscle-'.' 

71.  What  else  dues  it  supply  besides  these  five  muscle-? 

72.  Musculo-cutaneous  nerve  supplies  how  many  muse 

73.  Name  them. 

74.  'What  else  does  it  supply  besides  these  muscle-'.' 

75.  What  nerve  supplies  the  integument  on  external  border  of  the  foot? 

76.  From  what  plexu.-? 

77.  How  is  the  short  saphenous  formed? 

78.  The  internal  popliteal  nerve  supplies  how  many  muscles? 

79.  The  posterior  tibial  supplies  how  many? 

80.  The  posterior  tibial  divides  into  how  many  branches? 

81.  How  many  muscles  does  the  internal  plantar  supply? 

82.  Xame  those  it  supplies  in  the  1st,  2nd  and  3rd  layers. 

83.  Xame  those  supplied  by  the  external  plantar. 

84.  Give  the  cutaneous  nerve  supply  of  the  foot. 

85.  What  muscle  arises  just  below  the  insertion  of  the  Gluteus  maximus? 

86.  The  small  sciatic  comes  from  what  nerve-? 

87.  The  pudic  comes  from  what  nerves? 

88.  The  great  sciatic  comes  from  what  nerves? 

89.  The  superior  gluteal  comes  from  what  nerves? 

90.  The  inferior  gluteal  comes  from  what  nerves? 

91.  What  other  nerve  comes  from  the  same? 

92.  What  other  one  comes  from  the  same  one  as  the  superior  gluteal? 

93.  Give  the  relations  of  the  common  femoral  artery. 

94.  (Jive  the  relations  of  the  superficial  femoral  artery. 

95.  Give  the  relations  of  the  profunda  artery. 

96.  What  are  the  divisions  of  the  abdominal  aorta? 

97.  The  common  iliac  divides  into  what  branches? 

98.  The  internal  iliac  divides  into  what? 

99.  Xame  the  branches  of  the  anterior  trunk. 

100.  Xame  the  branches  of  the  posterior  trunk. 

101.  The  external  iliac  continues  as  what? 

102.  What  structures  ]>a>-  out  of  the  Greater  and  into  the  Lesser  sacro- 
sciatic  foramen? 

103.  What  passes  through  the  obturator  foramen? 

104.  What  is  inserted  into  the  digital  fossa? 

105.  Xame  the  ligaments  of  the  knee-joint. 

loti.   What  structures  pass  under  Poupart's  ligament? 

107.  "Who  was   Poupart? 

Ih    was  a  Frenchman.     Lived  1661-1709. 

108.  What  structures  pass  through  Hunter's  canal? 
K i'.i.  Who  was  Hunter? 

Wa-  British,  172s-17'.i::. 

110.  Hound  Hunter's  canal. 

111.  Hound  the  popliteal  space. 


228 


ANATOMY    IN    A    NUTSHELL. 


112.  WhyJ  called  popliteal? 

113.  Give   contents. 

114.  Name  the  Ligaments  of  the  ankle. 

115.  What  forms  the  crucial  anastomosis? 

116.  What  muscles  form  the  tendo  Achillis? 

117.  Why  is  the  Plantaris  so  called? 

118.  How  many  bones  in  the  foot? 
Hi).    Describe  the  fascia  lata. 

PLATE  XC. 


HEPATIC 


SPERMATIC  VEIN 


SPERMATIC     ARTERY 


RIGHT  LUMBAR  ARTERY 


LEFT     PHRENIC 

GASTRIC    ARTERY 

-SPLENIC    ARTERY 
LEFT  SUPRARENAL 

RENAL  ARTERY, 

RENAL  VEIN 
SUPERIOR         MESENTERY,  ' 


INFERIOR   MESENTERY  ARTERY 


EXTERNAL     ILIAC^ 

^INTERNAL     ILIAC  ' 

Showing  the  Great  Vessels  Below  the  Diaphragm. 

L20.  Describe  the  deep  fascia  of  the  leg. 

l_'l.  Describe  the  ilio-tibia)  band. 

122.  What  muscles  compose  the  Quadriceps  extensor  cruris? 

1  J.'!.  The  tendon  of  what  long  muscle  passes  directly  across  the  sole  of  the 

foot? 

L24.  Describe  the  saphenous  opening. 

125.  Why  called  saphenous? 

120.  Describe  the  external  abdominal  ring. 


ANATOMY    IN    A    NUTSHELL. 


229 


127.  Describe  Poupart's  ligament, 

128.  Describe  Gimbernat's  ligament. 


PLATE  X(T. 


SUPRARENAL  CAPSULE 


EXTERNAL  ILIAC  GLANDS 


LUMBAR  GLANDS 


COMMON   ILIAC  ARTERY 


SACRAL  GLANDS. 


t!  INTERNAL  ILIAC  GLANDS. 


,DEEP  INGUINAL  GLANDS 

V 


LYMPHATICS    OF     PENIS 


Showing  the  Abdominal  Aorta  and  its  Terminal  Branches. 

129.  Describe  Petit 's  triangle. 

130.  Describe  the  trianglar  ligament  of  the  abdomen. 

131.  What  muscles  are  attached  to  the  intermuscular  septa  of '  fascia'  lata? 


230  WAToMY    IX    A    NUTSHELL. 

1 :'.'_'.   Describe  interna]  abdominal  ring. 

133.  What  does  the  word  hernia  mean? 

134.  What  muscles  make  the  external  rotators  of  hip? 

135.  What  muscles  make  the  internal  rotators  of  hip? 

L36.  Show  how  the  external  popliteal  nerve  gets  to  the  front  of  the  leg. 

137.  The  length  of  the  femur  is  what  part  of  the  [<  agth  of  the  body? 

138.  Describe  the  linca  asju  ra  and  what  muscles  are  attached  to  it. 

139.  At  what  angle  dots  tin  neck  join  with  shaft  of  femur? 
1  li).  Give  function  and  location  of  patella. 

141.    Describe  the  knee-joint. 

1  l'_\   What  passes  through  the  Obturator  forami  n? 

I  13.   Why  so  called? 

!  II.   Give  dimensions  of  pelvic  cavity. 

1  lo.    1  )escribe  the  lumbal'  fascia. 

1  Hi.   The  sacral  plexus  continu.es  as  what'.' 

147.  Great  sciatic  divides  into  what  nerves? 

1  IV   .Name  four  kinds  of  hernia. 

149.  Name  the  different  kind  of  joints  found  in  the  body. 

1 50.  Why  does  the  arm  admit  of  greatf  r  motion  than  the  leu'.' 

151.  What  is  the  sustentaculum  tali? 

152.  What  is  the  receptaculum  chyli? 

153.  Where  are  the  anterior  and  posterior  circumflex  arteries? 

154.  Where  are  the  internal  and  externa!  circumflex  arteries? 
1.").").   What  is  the  Biceps  cubiti? 

156.  What  muscle  is  attached  to  all  tarsal  bones  but  one? 

157.  -Name  the  muscles  attached  to  each  tarsal  bone. 

158.  Give  articulation  of  each  tarsal  bone. 

159.  Name  the  spinous  processes  of  the  ilium. 

160.  What  is  attached  to  each? 
ltd.  Give  meaning  of  trochanter. 

162.  (live  blood  supply,  ossification,  articulation  and  attachment  of  mus- 
cle,- io  the  os  innominatum. 

lii:i.  Same    for   femur. 

164.  Sin ne  for  tibia. 

165.  Same    for   fibula. 

166.  Same  for  tarsus. 

167.  Same  for  metatarsus. 
L68.  Same  for  phalanges. 

169.  Same  tor  patella. 

170.  Same  for  sacrum. 

171.  Same  for  coccyx. 

172.  Give  branches  of  femoral  artery. 

1  7:;.  ( rive  branches  of  popliteal  artery. 

17-1.  Give  branches  of  anterior  tibial  artery. 

175.  Give  branches  of  posterior  tibial. 

176.  Give  branches  of  dorsalis  pedis. 


ANATOMY    IN    A    NUTSHELL. 


231 


177.  Give  branches  of  peroneal  artery. 

178.  Give  plantar  arch. 

179.  This  arch  gives  off  what  branches? 


PLATE  XCII. 

INTERCLAVICULAR  NOTCH. 


STERNO-MASTUIU. 


COSTAL    CARTILAGE 


APONEUROSES      OF      ABDOMINAL    MUSCLES. 

Anterior  View  of  Sternum. 

L80.  Which  is  the  larger    external  or  internal  plantar  artery? 

181.  Which  is  the  larger     the  external  or  internal  plantar  nerve? 

182.  Give  relation   of  popliteal   artery. 


232  ANATOMY    IN    A    NUTSHELL. 

183.  Give  relation  of  anterior  tibial  artery. 

184.  Give  relation  of  posterior  tibial  artery. 

185.  Give  relation  of  peroneal  artery. 

186.  Give  relations  of  dorsalis  pedis  artery. 


LESSON  LXIII. 
The  Thorax.      (Plate  XC1V.) 

The  thorax  is  formed  by  thirty-seven  bones,  namely,  the  twenty-four  ribs 
the  twelve  dorsal  vertebrae,  and  the  sternum.  The  thorax  is  a  conical  cavity, 
broad  below,  narrow  above,  flattened  from  before  backward,  and  longest  pos- 
teriorly. Its  posterior  boundary  is  formed  by  the  bodies  of  the  dorsal  ver- 
tebrae and  the  posterior  portion  of  the  ribs,  thus  making  it  concave  verti- 
cally with  a  high  ridges  on  either  side.  The  lateral  boundaries  are  convex, 
being  formed  by  the  ribs  and  Intercostal  muscles.  The  anterior  boundary, 
which  slopes  down  and  forward,  is  formed  by  the  sternum  and  the  costal  car- 
tilages. 

The  upper  opening  of  the  thorax  is  broadest  transversely  and  is  formed  by 
the  first  dorsal  vertebra  posteriorly,  first  ribs  laterally,  and  the  upper  margin 
of  the  manubrium  anteriorly.  The  upper  border  of  the  manubrium  is  on  a 
level  with  the  second  dorsal  vertebra.  In  the  female  the  sternum  is  shorter 
than  in  the  male,  the  ribs  more  movable,  and  the  thorax  is  smaller.  The  upper 
margin  of  the  manubrium  is  on  a  lower  level  than  in  the  male.  There  are  forty 
structures  passing  through  the  superior  opening  of  the  thorax.  There  are 
three  pairs  of  muscles  that  pass  through  this  upper  opening  in  the  thorax. 
Sterno-thyroid,  Sterno-hyoid  and  Longus  colli  muscles,  making  six  muscles. 
The  arteries  that  pass  through  the  superior  opening  of  the  thorax  are  the  (1) 
innominate,  (2)  left  common  carotid  and  (3)  left  subclavian,  (4)  and  (5)  the  two 
internal  mammary  and  (6)  and  (7)  the  two  superior  intercostal.  There  are 
fifteen  nerves  that  pass  through  this  opening:  (1)  and  (2)  the  two  Pneumo- 
gastric,  (3)  and  (4)  the  two  phrenic,  the  six  cardiac  and  the  two  sympathetic 
nerves,  the  anterior  branches  of  the  two  first  dorsal  nerves,  and  the  recurrent 
laryngeal  nerve  of  the  left  side  make  fifteen.  The  veins  that  pass  through  this 
superior  opening  are  the  right  and  left  innominate  and  the  inferior  thyroid 
veins,  making  four  veins.  There  are  eight  unclassified  structures  that  pass 
through  this  opening  in  the  thorax:  Remains  of  thymus  gland,  trachea,  oesoph- 
agus, thoracic  duct,  apex  of  each  lung,  and  pleurae.  Then  the  six  muscles, 
fifteen  nerves,  seven  arteries, four  veins,  and  eight  unclassified  structures  make 
the  forty  structures  which  pass  through  the  superior  opening  of  the  thorax. 

The  Lower  opening  of  the  thorax  is  widest  transversely  and  slopes  down- 
ward and  backward.  It  is  formed  by  the  last  dorsal  vertebra  posteriorly,  and 
the  seventh  to  the  eleventh  costal  cartilages  laterally,  and  the  ensiform  car- 
tilage anteriorly.  The  Diaphragm  separates  the  thoracic  cavity  from  the 
abdominal    cavity. 


ANATOMY    IN    A    XUTSHELL. 


233 


Diaphragm.     (Plate  LXXII.) 

The  word  diaphragm  is  a  Greek  word  meaning  a  partition  wall.  It  is  a 
musculo-fibrous  septum,  situated  between  the  upper  one-third  and  the  lower 
two-thirds  of  the  trunk.  It  separates  the  thoracic  cavity  from  the  abdominal 
cavity/    It  is  the  floor  of  the  former  and  the  roof  of  the  latter,  its  general  shape 

PLATE  XCTII. 

CLAVICULAR    NOTCH 
STERNO      HYOID, 
STERNO    THYRO 


FIRST    COSTAL 
CARTILAGE 


TRIANGULARIS   STERNI 


ENSIFORM  APPENDIX 


Posterior  View  of  Sternum. 

is  somewhat  like  that  of  an  umbrella  or  an  irregular  dome.  The  upper  surface 
of  it  is  covered  with  the  right  and  left  pleura,  he!  ween  the  two  pleura'  it  is  cover- 
ed with  the  pericardium.  Its  circumference  is  elliptical  in  form,  highesl  at  the 
ensiform  cartilage.     The  highest  part  of  all  the  diaphragm  is  od  the  righl  side 


ANATOMY    IX    A    NUTSHELL. 

immediately  above  the  liver.  This  is  a  litth  higher  than  the  left  side.  The 
lowest  part  of  it  is  the  righl  crus  which  reaches  in  the  fourth  lumbar  vertebra. 
The  under  surface  is  cov<  red  with  p(  ritone  um.  1 1  is  One  of  the  so-called  double 
Ik  Ui<  (I  musch  s.  1 1  has  its  origin  in  frorrt  from  th<  <  asiform  cartilage,  from  the 
sides,  from  the  under  surfaces  of  the  cartilages  and  bony  portion  of  the  six  or 
seven  lower  ribs  interdigitating  with  the  Transversalis  muscle,  also  from  the 
two  aponeurotic  arches  called  the  ligamentum  arcuatum  externum  el  internum. 
The  last  one  is  the  covering  of  the  Psoas  magnus,  the  first  one  is  the  covering  of 
the  Quadratus  lumborum.  Behind  ii  is  connected  to  the  spine  by  two  crura 
or  legs,  the  right  one  is  the  longer  i  xtending  from  the  anterior  surface  of  the 
bodi<  s  and  intervertebral  substance  of  the  thrc  e  or  four  upp<  r  lumbar  vertebrae; 
tin  left  one  from  the  anterior  surfaces  of  th<  two  upper  ones.  From  this  origin  it 
-  to  the  central  or  cordiform  tendon  which  consists  of  three  leaflets,  the 
righl  one  is  the  largest,  the  left  on<  the  smallest,  and  the  middle  one  is  inter- 
im diate  in  size.  On  each  sid(  of  tin  ensiform  attachment  tin  re  is  a  weak  place 
which  may  be  brok<  n;  th<  n  we  nay  have  what  is  called  a  phrenic  or  diaphrag- 
matic hernia.  Some  of  the  contents  of  the  abdomen  protrude  into  the  chest, 
or  ptts  in  the  mediastinum  may  descend  through  it  into  the  abdominal  cavity. 
The  diaphragm  has  three  large  and  several  small  natural  foramina.  The  one 
mosl  posterior  is  really  not  in  the  diaphragm  bui  between  the  two  crura  which 
arc  joined  posteriorly  by  a  tendinous  band.  This  is  called  the  aortic  opening, 
and  transmits  the  aorta,  vena  azygos  major,  the  thoracic  duct,  and  sometimes 
the  left  sympathetic  nerve;  when  this  nerve  does  not  pass  through  this  open- 
ing it  goes  through  the  left  crus.  The  vena  azygos  major  occasionally  goes 
through  the  right  crus.  The  second  large  opening  is  in  front,  and  a  little  to  the 
left  of  the  aortic  opening;  it  transmits  the  oesophagus  and  the  pneumogastric 
oerves.  Th<  left  pneumogastric  passes  in  front  of  the  oesophagus.  The  right 
one,  which  passes  b;  hind  it,  goes  into  the  solar  plexus,  which  is  situated  behind 
the  stomach.  The  third  large  opening  is  farther  in  front  than  the  others  and 
lies  in  the  c<  ntral  tendon.  Ii  is  son u  what  quadrilateral  in  form  and  is  called 
the  foramen  quadratum;  the  inf<  rior  v<  na  cava  passes  through  it. 

The  smaller  openings  are  through  the  crura.  Those  in  the  right  crus  transmit 
the  great*  r  and  less*  r  splanchnics  and  the  sympathetic  nerves  of  the  right  side, 
occasionally  the  vena  azygos  major.  The  left  cms  transmit  the  vena  azygos 
minor,  the  greater  or  lesser  splanchnic  nerves  of  the  left  side  and  the  sympathe- 
tic nerve  of  the  left  side  when  it  does  not  pass  through  the  aortic  opening.  The 
blood  supply  of  the  diaphragm  is  derived  from  the  two  phrenic,  the  internal 
mammary,  and  the  lower  intercostal  arteries.  The  phrenic  arteries  are  two 
small  arteries  which  may  arise  separately  from  the  aorta  above  the  coeliac  axis. 
<  hien  .me  is  derived  from  the  aorta  and  the  other  from  the  renal  arteries.  They 
very  rarely  arise  as  two  separate  vessels  from  the  aorta.  The  nerve  supply  is 
the  phrenic  which  comes  from  the  third,  fourth,  and  fifth  cervical  nerves.  The 
phrenic  plexus  also  helps  to  supply  it.  This  plexus  is  made  by  the  phrenic 
nerve  and  branches  from  the  semilunar  ganglion  of  the  solar  plexus.  The 
laity  call  the  diaphragm  the  midriff,  which  comes  from  the  Saxon  words  which 
mean  the  middle  of  the  belly.     The  solar  plexus  or  abdominal  brain  and  the 


ANATOMY    IV    A    NUTSHELL 


235 


phrenic  plexus  are  situated  near  the  diaphragm.  The  former  behind  the 
stomach  and  the  latter  formed  by  branches  from  it.  These  plexus  or  plexuses 
belong  to  the  great  sympathetic  system,  which  govt  rns  tl  ritary  actions. 

PLATE  XClV. 


FLOA- 


Boxes  of  i  he  Thorax. 


ere  blow  on  the  head  may  knock  a  man  senseless  bul  he  Mill  lives.  His 
heart  ami  lungs  still  ad.  being  governed  by  the  sympathetic  system,  but  if  he 
receive^  a  severe  blow  upon  the  diaphragm  it  may  produce  instant  death.  The 
pugilist  has  learned  this  much  about  anatomy  and  if  he  were  not  trained  to  the 


236  ANATOMY    IN    A    NUTSHELL. 

hour  more  would  be  killed  than  are  by  this  so-called  solar  plexus  blow.  The 
diaphragm  is  the  chief  muscle  of  respiration.  The  lower  ribs  may  fall  down 
thus  drawing  the  diaphragm  out  of  its  natural  position,  in  this  way  somewhat 
obstructing  the  passing  of  the  blood  through  the  aorta.  I  have  known  of  one 
case  in  which  the  diaphragm  was  pulled  down  by  the  lower  ribs  causing  an 
irregular  action  of  the  heart.  As  soon  as  they  were  replaced  the  heart  acted  in 
a  natural  manner.  Tight  lacing,  or  any  cause  whatsoever  which  will  impair 
the  natural  action  of  the  diaphragm  will  cause  much  pain.  Man  is  the  only 
animal  in  which  the  transverse  diameter  of  the  diaphragm  is  greater  than  the 
antero-posterior.  It  begins  to  be  developed  about  the  ninth  week  of  fetal  life 
and  grows  from  the  circumference  to  the  central  tendon.  All  mammals  or 
milk-giving  animals  have  a  diaphragm.  Man  and  horse  are  examples  of  land 
animals,  the  whale  and  the  sea  cow  are  examples  of  water  animals  which  have 
diaphragms.  Birds  possess  a  rudimentary  form,  which  is  best  shown  in  the 
abteryx. 


LESSON  LXIV. 

The  muscles  which  help  the  Diaphragm  in  tranquil  inspiration  are  (1) 
Intercostals,  (2)  Levatores  costarum,  and  (3)  The  Scaleni.  Those  which  help 
it  in  forced  inspiration  are  (1)  Trapezius,  (2)  Pectoralis  minor,  (3)  Pectoralis 
major  (?)  (4)  Serratus  posticus  superior,  (5)  Serratus  posticus  inferior,  (6) 
Rhomboideus  major,  (7)  Rhomboideus  minor,  (8)  Serratus  magnus,  (9)  Sterno- 
cleido-mastoid,   (10)   Ilio-costalis,   (11)   Quadratus  lumborum. 

Tranquil  expiration  is  caused  by  the  elasticity  of  the  lungs  and  that  of  the 
chest  walls.  The  muscles  of  forced  expiration  are  (1)  External  oblique,  (2)  In- 
ternal oblique,  (3)  Transversalis,  (4)  Rectus  abdominis,  (5)  Internal  inter- 
costals, (6)  Triangularis  sterni. 

The  sternum  (Plates  XCTI-XCIII.)  is  about  six  inches  long  and  is  situated 
in  the  median  line  of  the  thorax  in  front.  It  is  flat  anteriorly  and  concave  pos- 
teriorly. It  is  broadest  above  and  pointed  below,  and  constricted  at  the  junc- 
tion of  the  manubrium  with  the  gladiolus.  The  manubrium  or  first  piece  of  the 
sternum  is  narrow  below,  but  broad  above.  The  anterior  surface  of  the  manu- 
brium is  concave  vertically  but  convex  transversely.  The  Pectoralis  major 
and  Sterno-cleido-mastoid  are  attached  to  the  lateral  aspect  of  this  surface. 
The  upper  border  of  this  part  forms  the  interclavicular  notch,  on  each  side  of 
which  is  an  oval  facet  for  the  articulation  of  the  clavicle.  The  lateral  border 
articulates  above  with  the  cartilage  of  the  first  rib  and  below  with  the  upper 
poit ion  of  the  cartilage  of  the  second  rib.  The  lowrer  border  articulates  with 
the  gladiolus.  The  posterior  surface  is  concave  and  gives  attachment  to  the 
Sterno-hyoid  and  Sterno-thyroid  muscles.  The  gladiolus  or  second  portion  is 
longer,  narrower  and  thinner  than  the  manubrium.  It  is  broadest  below. 
The  anterior  surface  gives  attachment  to  the  Pectoralis  major.  Three  trans- 
verse lines,  indicating  the  original  divisions  of  the  gladiolus  into  four  portions, 
pass  from  the  third,  fourth,  and  fifth  articular  facets  across  the  bone.  These 
lines  are  not  so  well  marked  on  the  posterior  surface.     This  surface  is  concave 


ANATOMY    IN    A    NUTSHELL. 


237 


and  gives  attachment  to  the  Triangularis  sterni  muscle.  The  lateral  border 
of  the  gladiolus  articulates  with  the  cartilages  of  the  second,  third,  fourth,  fifth, 
sixth,  and  seventh  rib;  however  the  second  and  seventh  cartilages  articulate 
partly  with  the  bones  above  and  below.  This  portion  of  the  bone  articulates 
with  the  manubrium  above  and  the  ensiform  or  xiphoid  appendix  below. 

The  ensiform  appendix,  cartilaginous  hi  youth  but  is  partly  ossified  above 
in  the  adult.  The  chondro-xiphoid  ligament  is  attached  to  its  anterior  surface, 
while  the  Diaphragm  and  the  Triangularis  sterni  are  attached  to  its  posterior 
surface.  It  articulates  above  with  the  gladiolus.  Laterally  the  aponeurosis 
of  the  abdominal  muscles  are  attached.  The  superior  angle  of  the  lateral 
border  has  a  demi-facet  for  the  cartilage  of  the  seventh  rib.  Its  apex  may  be 
bifid  below  or  may  present  a  foramen,  and  it  gives  attachment  to  the  linea 
alba. 

Attachment  of  Muscles: — Nine  pairs  and  one  single  muscle.  The 
Pectoralis    major,    Sterno-cleido-mastoid,    Sterno-hyoid,    Sterno-thyroid,    Tri- 

PLATE  XCV. 


LATERAL  MASS 
COSTOTRANSVERSE 
FORAMEN 


SURFACE 


FORAMEN  FOR 
VERTEBRAL  ARTERY 


The  Atlas 

annularis  sterni,  aponeurosis  of  the  External  oblique,  Internal  oblique,  Trans- 
versalis,  Rectus  muscles,  and  Diaphragm. 

Ossification: — From  six  centers.  One  for  the  manubrium  (fifth  or 
sixth  month.)  One  for  each  of  the  four  pieces  of  the  gladiolus.  The  ones 
for  the  first  two  pieces  of  the  gladiolus  appear  at  the  sixth  or  SEVENTH 
month.  The  one  for  the  third  piece  appears  at  the  ninth  month,  and  the 
one  for  the  fourth  piece  appears  during  the  first  year  after  birth.  The 
one  for  the  ensiform  appendix  appears  between  the  SECOND  and  eighteenth 
years.  The  manubrium  and  the  lower  three  pieces  of  the  gladiolus  may  have 
two  centers  each,  thus  making  ten  centers  of  ossification  for  the  sternum. 
The  pieces  of  the  gladiolus  join  at  about  the  age  of  puberty,  while  the  glad- 
iolus rarely  joins  the  manubrium  and  the  ensiform  remains  cartilaginous  even 
in  advance  life. 

Articulation. — With  the  clavicles  and  seven  costal  cartilages  on  each 
side. 


238  ANATOMY    IN    A    NUTSHELL. 

Blood  Supply. — Internal  mammary  arteries  through  its  sternal  and  per- 
foratum branches,  also  twigs  from  the  aortic  intercostal  arteries. 

Heart. 

The  covering  of  the  heart  is  called  the  Pericardium.  Besides  covering  the 
lu  ait  it  encloses  the  origin  of  the  great  vessels.  It  is  situated  behind  the  sternum 
from  the  third  to  the  seventh  costal  cartilages  (inclusive)  and  between  the  two 
pleurae.  It  forms  a  closed  sac.  the  base  of  which  is  attached  to  the  central 
tendon  and  adjoining  muscular  substance  of  the  Diaphragm,  and  it  extends 
more  to  the  1<  ft  than  to  the  right.  The  apex  of  the  pericardium  is  directed  up- 
ward and  surrounds  the  great  vessels  for  about  two  inches.  Behind  the  per- 
icardium are  (1)  the  two  bronchi.  (2)  the  esophagus,  (3)  descending  aorta.  In 
front  are  f  1 )  the  margin  of  the  lungs,  (2)  remains  of  the  thymus  gland  (above), 
(3)  areolar  tissue  (below).  (4)  the  sternum.  On  the  sides  it  is  covered  by  the 
pleura  and  the  phrenic  nerve. 

The  pericardium  is  composed  of  two  layers,  first  a  fibrous,  second  a  serous. 
Tin:  fibrous  OB  external  layer  is  strong  and  dense.  It  sends  prolongations 
around  the  gr<  at  vessels  which  join  their  external  coats.  It  also  sends  a  diverti- 
culum upward  on  each  side  of  the  ascending  aorta.  The  one  on  the  left  side  of 
the  ascending  aorta  passes  between  the  left  pulmonary  artery  and  the  arch  of 
the  aorta  to  the  ductus  arteriosus  where  it  ends  in  a  blind  extremity.  The  one 
on  the  light  side  of  the  ascending  aorta  passes  between  this  vessel  and  the  super- 
ior vena  cava,  and  it  also  ends  in  a  blind  extremity.  This  fibrous  layer  is  at- 
tached below  to  the  central  tendon  and  muscular  substance  of  the  Diaphragm. 
Two  ligaments,  the  superior  sterno-pericardial  and  the  inferior  sterno-peri- 
cardial,  connect  it  with  the  sternum  anteriorly. 

Tin.  serous  ok  internal  layer  consists  of  two  portions,  first  a  visceral, 
and  second  a  paiital.  The  visceral  layer  covers  the  heart  and  the  great  v<  ssels 
for  about  an  inch  and  a  half  and  then  is  reflected  upon  the  inner  surface  of  the 
fibrous  layer  forming  the  parietal  portion.  The  pulmonary  artery  and  the 
aorta  are  enclosed  in  a  single  tube  of  pericardium.  Behind  this  tube  there  is  a 
passagi  called  the  transv<  rse  p<  ricardial  sinus.  The  pericardium  only  partially 
covers  the  vena  cava  and  pulmonary  veins,  so  that  on  each  si  le  of  these  struc- 
tures  iIk  re  i-  a  cul-de-sac.  The  one  on  the  left  side  is  known  as  the  oblique 
.-iin  s,  the  one  (.n  the  righi  as  the  straight  sinus.  The  vestigial  fold  of  Marshall 
lies  between  the  left  pulmonary  artery  and  the  subadjacent  pulmonary  vein, 
thus  enclosing  the  remains  of  the  lefl  superior  vena  cava.  This  left  superior 
vena  cava  is  a  fibrous  cord  which  may  be  traced  upward  te>  the  left  superior 
intercostal  vein  and  downward  to  the  coronary  sinus  and  known  as  the  oblique 
v<  in  of  Marshall. 

Blood  Supply. — The  art<  ri<  s  to  the  pericardium  come  from  the  descending 
thoracic  aorta  and  the  internal  mammary  with  its  musculo-phrenic  branch. 

Nerve  Supply.  Xerxes  to  the  pericardium  are  from  the  tenth,  phrenic, 
and  sympath)  tic.  The'  nerve  supply  to  the  pericardium, the  heart, the  pleurae, 
and  the  lungs,  is  derived  from  these  three  sources.  As  said  above'  they  all  go 
tei  the  |  (  ricardium.     The-  tenth,  the  sympathetic  and  pe>ssibly  the  phrenic  pass 


ANATOMY    IN    A    NUTSHELL. 


239 


to  the  heart.     The  tenth  and  sympathetic  go  to  the  lungs  substance,  while  the 
phrenic  and  sympatheic  pass  to  the  pleura. 


LESSON  LXV. 

The  heart  (Plate  CXXVIII.)  is  situated  in  the  middle  mediastinum  be- 
tween the  spinous  processes  of  the  fourth  dorsal  and  eighth  dorsal  vertebra 
posteriorly.  Its  apex  is  directed  downward  and  forward  to  the  left,  and  lies 
against  the  fifth  intercostal  space  three -quarters  of  an  inch  to  the  inn<  r  sid    of 


PLATE  XCVI. 


ROUGH  SURFACE 
FOR 
CHECK  LJGAMEW. 

SUP.  ARTIC. 
PROC. 


ODONTOID 
PROC. 

ARTIC.  GROOVE  FOR 
TRANSVERSE  LIG. 


LAMI 


SPINOUS  PROC 


Posterior  View  of  Axis. 

the  left  nipple  and  an  inch  and  a  half  below  the  same.  The  heart  lies  obliquely 
behind  the  lower  tw<  -thirds  of  the  sternum,  extending  about  three  inches  to 
the  left  of  the  median  line  and  one  and  a  half  inches  to  the  right.  Its  anterior 
surface  consists  mostly  of  the  light  ventricle  and  a  part  of  the  left  ventricle. 
It  is  convex  and  looks  upward  and  forward.  Its  posterior  surface  consists 
mostly  of  the  left  ventricle  and  rests  upon  the  Diaphragm.  This  surface  is 
flattened.  The  right  border  of  the  heart  is  long  and  thin,  while  the  left  is  short 
and  thick. 

The  average  weight  of  the  heart  is  about  eleven  ounces.  In  the  male  it 
weighs  from  ten  to  twelve  ounces,  while  in  the  female  its  weight  is  from  eight 
to  ten.  The  adult  heart  is  five  inches  long  by  three  and  a  half  wide,  by  two 
and  a  half  thick.  It  is  divided  into  four  chambers,  namely,  the  right  and  left 
auricles  and  the  right  and  left  ventricles.  The  right  side  of  the  heart,  which  is 
more  superficial  and  is  called  the  venous  heart,  is  separated  from  the  left  side 
of  the  heart,  which  is  deeper  and  is  called  the  arterial  heart,  by  a  longitudinal 
septum, and  each  of  these  lateral  halves  are  divi  led  bya  transverse  septum,thus 
making  the  auricles  and  ventricles. 

These  four  divisions  of  the  heart  are  indicated  by  grooves  on  its  surface. 
The  apex  of  the  heart  is  formed  entirely  by  the  left  ventricle.  These  grooves 
on  the  surface  of  the  heart  contain  the  coronary  arteries, cardiac  veins, lymphat- 
ics, nerves  and  fat. 


240  ANATOMY   IN   A    NUTSHELL. 

The  right  auricle  has  a  capacity  of  about  two  ounces.  It  is  larger  than  the 
left  auricle  but  its  walls  arc  thinner.  It  consists  of  two  main  parts,  first  a  sinus 
or  atrium  which  is  large  and  lies  between  the  superior  vena  cava  above  and  the 
inferior  vena  cava  below  and  has  postero-internally  to  it  the  left  auricle.  The 
second  pari  is  the  auricular  appendix,  which  is  small  and  conical  projecting  for- 
ward and  to  the  left  over  the  root  of  the  aorta.  The  inner  surface  of  the  auricle 
is  smooth  except  in  this  auricular  appendix  and  the  adjacent  part  of  the  right 
wall  of  the  sinus.  At  this  point  it  is  thrown  into  parallel  ridges  called  musculi 
pectinati.     (Plate  CXXIX.) 

The  right  auricle  has  the  following  points  for  consideration: 

1.  The  opening  of  the  superior  vena  cava,  which  is  at  the  upper  and  back 
part  of  the  auricle  and  is  directed  downward  and  forward.  The  blood  from  the 
superior  vena  cava  flows  toward  the  auriculo-ventricular  opening. 

2.  The  opening  of  the  inferior  vena  cava  is  larger  than  the  superior  and  is 
at  the  lower  part  of  the  auricle  near  the  auricular  septum.  The  blood  from  the 
inferior  vena  cava  is  directed  upward  and  inward  towards  the  auricular  septum. 

3.  There  is  small  projection  between  the  superior  vena  cava  and  the  in- 
ferior vena  cava  called  the  tubercle  of  Lower.  Its  function  is  to  direct  the  blood 
from  the  superior  vena  cava  towards  the  auriculo-ventricular  opening. 

4.  There  is  an  opening  between  the  inferior  vena  cava  and  the  auriculo- 
ventricular  opening  called  the  coronary  sinus.  It  is  guarded  by  a  valve  called 
coronary  or  Thebesii.  It  receives  blood  from  the  substance  of  the  heart  and  it 
is  constricted  where  it  joins  the  great  coronary  vein. 

5.  The  auriculo-ventricular  opening  is  somewhat  oval  and  about  an  inch 
in  diameter  and  lies  between  the  right  auricle  and  right  ventricle.  It  is  sur- 
rounded by  a  fibrous  ring  covered  by  the  lining  membrane  and  is  guarded  by 
the  Tricuspid  valve. 

6.  The  foramina  of  Thebesii  are  small  openings  of  the  venae  cordis  minima? 
which  return  blood  from  the  substance  of  the  heart. 

7.  A  semilunar  fold  of  the  endocardium  which  lies  between  the  auriculo- 
ventricular  opening  and  the  anterior  margin  of  the  opening  of  the  inferior  vena 
cava  is  called  the  Eustachian  valve.  In  the  fetus  this  valve  is  large  and  directs 
the  blood  from  the  inferior  vena  cava  through  the  foramen  ovale  into  the  left 
auricle.      It  may  be  present  or  it  may  be  absent  in  the  adult. 

8.  The  coronary  valve  also  called  Thebesii  is  a  semicircular  fold  of  endo- 
cardium which  guards  the  opening  of  the  coronary  sinus.  This  valve  may  be 
double  and  it  prevents  regurgitation  into  it  (hiring  systole1  of  the  auricle. 

9.  The  fossa  ovalis  is  a  remains  of  fetal  life.  It  is  an  oval  depression  lying 
on  the  lower  part  of  the  auricular  septum  marking  the  position  of  the  foramen 
ovale.     There  may  be  a  small  foramen  in  this  fossa  throughout  life. 

10.  The  annulus  ovalis  is  a  prominent  margin  of  the  foramen  ovale  and  is 
best   marked  above  and  at   the  sides,  while  below  it  is  wanting. 

11.  The  musculi  pectinati  are  small  muscular  folds  which  are  found  in  the 
auricular  appendix  and  the  adjacent  pari  of  the  sinus  venosum.  They  end  in 
a  vertical  ridge  posteriorly  called  the  crista  terminalis  of  His. 

The  right  venrtiele  extends  from  the  right  auricle  nearly  to  the  apex  of  the 


ANATOMY    IN    A    NUTSHELL. 


241 


heart.  Its  walls  are  one-third  as  thick  as  those  of  the  left  ventricle,  and  it 
holds  about  three  ounces.  Its  posterior  surface  rests  upon  the  Diaphragm 
forming  a  small  part  of  the  back  of  the  heart,  while  its  anterior  surface  forms 
most  of  the  front  of  the  heart. 

1.  The  conus  arteriosus  or  infundibulum  is  a  conical  pouch  at  the  upper 
and  left  angle  of  the  ventricle,  from  which  the  pulmonary  artery  arises. 

2.  The  auriculo-ventrieular  opening  has  been  described  with  the  auricle. 

3.  The  opening  of  the  pulmonary  artery  which  lies  at  the  summit  of  the 
infundibulum  is  circular.     It  is  guarded  by  the  pulmonary  semilunar  valves. 

4.  The  tricuspid  valve  consists  of  three  portions.  The  largest  of  these 
segments,  called  the  left  or  infundibular  flap,  lies  at  the  left  and  front  of  the 
opening.  The  right  flap  is  to  the  front  and  right,  while  the  third,  called  the 
posterior  or  septal  flap,  is  posteriorly.  The  center  of  each  of  these  flaps  is  thick, 
the  lateral  margins  are  thin. 

5.  The  chorda?  tendinae  are  fibrous  cords  which  are  attached  to  the  mar- 

PLATE  XCVII. 


A,  ARTIC.WVTH 
U^t?    ANT.  ARCH  0FA7LA5. 


BODY. 

Anterior  View  of  Axis. 

gins  and  ventricular  surfaces  of  each  of  these  flaps.  Three  or  four  are  attached 
t<>  the  liases  of  each  flap  and  are  continuous  with  the  fibrous  ring  which  surrounds 
the  auriculo-ventrieular  opening.  Four  to  six  pass  to  the  central  part  of  these 
flaps,  and  the  finest  and  most  numerous  go  to  the  free  margins  of  these  flaps. 

6.  Column;?  earneae  project  from  the  walls  of  the  ventricle  except  near  the 
pulmonary  opening.  They  are  divided  into  three  sets,  the  first  set  are  at- 
tached throughout  their  length  thus  forming  mere  ridges.  The  second  sel  called 
trabecular,  are  attached  to  their  ends  only,  thus  forming  arches,  while  the  third 
3e1 .  <;tlled  musculi  papillares,  are  attached  to  one  end  only,  thus  forming  pillars. 
These  musculi  papillares  are  two  in  number,  an  anterior  and  a  posterior,  and 
they  give  attachment  by  their  free  ends  to  the  chor.hr  tendinae.  Those  from 
the  anterior  one  pass  to  the  right  and  left  flaps,  while  those  from  the  posterior 
one  pass  to  the  right  and  septal  flaps.  A  few  of  the  chordae  tendinae  pass  to 
the  left  and  septal  flaps  from  the  septum. 

7.  The  semilunar  valves  (Plate  XCXXX.)  (pulmonary)  are  three  in  num- 
ber.    Two  anterior,  (a  righl  and  left),  and  one  posterior.     They  are  formed  by 


242  ANATOMY    IN    A    NUTSHELL. 

folds  of  fibrous  membrane,  covered  by  endocardium  below  and  by  the  inner 
arterial  coat  above.  The  convex  margin  of  each  valve  is  attached  to  the  inner 
coal  of  the  artery  where  it  joins  the  ventricle,  while  its  double  crescentic  border 
is  free  and  is  directed  upward.  The  corpus  arantii  are  small  nodules  situated 
at  the  center  of  each  free  margin.  Tendinous  fibers  radiate  from  the  corpus 
arantii  to  the  attached  margin  of  the  valve,  passing  throughout  the  entire 
valve  excepting  a  small  portion  on  each  side  of  the  corpus  arantii  called  the 
lunula.  At  this  point  the  valve  consists  of  lining  membrane  only.  When  the 
valve  closes  the  surfaces  of  the  lunula  come  in  contact  and  the  copora  arantii 
fill  the  interval  at  the  center.  Sinus  of  valsalva  is  a  pouch  behind  each  valve. 
8.  The  moderator  band  is  a  muscular  beam  running  across  the  left  ventricle 
obliquely. 


LESSON  LXVI 

The  left  auricle  like  the  right  auricle  has  two  parts,  a  sinus  or  atrium  and 

an  auricular  appendix.  This  auricle  is  smaller  but  has  thicker  walls  than  the 
right  one.  The  atrium  lies  behind  the  aorta  and  the  pulmonary  artery  and  is 
separated  from  the  right  auricle  by  the  auricular  septum  internally.  The  left 
auricular  appendix  is  longer  and  narrower,  and  more  curved  than  the  right 
one,  and  it  projects  forward  to  the  right  over  the  root  of  the  pulmonary  artery. 
The  left  auricle  presents  the  following  points: 

1 .  The  openings  of  the  four  pulmonary  veins,  two  on  each  side.  These 
veins  have  no  valves  and  carry  pure  blood.  There  may  be  five  pulmonary  veins 
or  only  three. 

2.  The  auriculo-ventricular  opening  is  smaller  than  the  one  on  the  right 
side.  It  is  surrounded  by  a  fibrous  ring  covered  by  endocardium  and  guarded 
by  the  mitral  valve. 

3.  The  musculi  pectinati  are  fewer  and  smaller  than  those  on  the  right  side 
and  are  confined  to  the  auricular  appendix. 

4.  On  the  auricular  septum,  just  above  the  fossa  ovalis  of  the  right  auricle, 
there  is  an  impression  which  is  bounded  below  by  a  crescentic  ridge  whose  con- 
cavity looks  upward. 

The  left  ventricle  is  longer  than  the  right  and  its  walls  are  about  three  times 
as  thick.  It  forms  most  of  the  posterior  surface  of  the  heart,  all  the  apex,  and 
a  small  part  of  the  left  side  of  the  anterior  surface. 

The  left  ventricle  presents  the  following  points: 

1.  The  auriculo-ventricular  opening  which  is  below  and  to  the  left  of  the 
aortic  opening  is  described  with  the  left  auricle. 

2.  The  aortic  opening  is  circular  and  is  guarded  by  the  semilunar  valves. 
It  i>  situated  in  front  and  to  the  right  of  the  auriculo-ventricular  opening. 

3.  The  mitral  or  bicuspid  valve  is  attached  to  the  margin  of  the  auriculo- 
ventricular  opening  similar  to  the  tricuspid  valve  on  the  right  side  of  the  heart, 
luit  is  stronger  and  thicker  than  the  tricuspid  valve.  Its  segments  or  flaps  are 
covered  by  <  ndocardium  ami  contain  a  few  muscle  fibers.  The  larger  flap  lies 
to   the   right   and   in   front    between   the  auriculo-ventricular  opening  and  the 


ANATOMY    EN    A    NUTSHELL. 


243 


aortic  opening.     The  smaller  flap  lies  to  the  left   and  behind.     The  smaller 
flaps  are  usually  found  where  the  two  larger  flaps  meet. 

4.  The  chordae  tendinae  are  thicker,  stronger,  and  less  numerous,  but  have 
a  similar  attachment  as  those  on  the  right  side 

5.  The  semilunar  valves  (aortic)  are  three  in  number,  a  right  posterior,  a 
left  posterior,  and  an  anterior  one.  They  are  larger,  thicker,  and  stronger 
than  those  on  the  right  side,  but  are  similar  in  structure  and  attachment.  Their 
corpora  arantii  and  lunula  are  more  distinct  than  those  of  the  pulmonary  semi- 
lunar valves.  Their  sinuses  of  valsalva  are  larger  than  those  on  the  right  side. 
The  right  coronary  artery  arises  from  the  anterior  sinus  and  the  left  coronary 
artery  arises  from  the  left  posterior  sinus. 

6.  The  columns?  carnea?  are  smaller  and  more  numerous  than  those  on  the 


PLATE  XCVIII. 


ANT.  TUBERCLE 


TRANSVERSE 
PROC. 


fORAUEN  FOP 
VERTEBRAL  ARTERY. 


PEDICLE. 


SPINOUS 
PROC. 


The  Fifth  Cervical  Vertebra. 

right  side  and  are  arranged  in  a  similar  manner.  On  the  posterior  wall  and  at 
the  apex  they  are  interlaced.  The  musculi  papillares  are  larger  than  those  on 
the  right  side,  one  of  which  comes  from  the  anterior  wall,  the  other  from  the 
posterior  wall.     The  chorda'  tendinae  arise  from  their  free  ends. 

7.  Just  under  the  aortic  opening  there  is  a  small  cavity  called  the  aortic 
vestibule. 

8.  The  ventricular  septum  is  thick  below  but  above  it  becomes  thinner  and 
losing  its  muscular  fibers  consists  only  of  fibrous  tissue  covered  by  endothelium. 

For  position  of  valves  of  the  heart  in  reference  to  the  chest  wall,  see  Plate 
XVII. 

The  structures  of  the  heart  consists  of  muscular  fiber-  and  fibrous  rii  gs 
The  muscular  structure  called  myocardium  Ls  formed  from  small  striated,  and 
quadrangular  muscular  cells  which  have  nude  i  joined  end  to  end  to  form  fibers 
and  tend  to  branch,  anastomosing  with  other  cells.  Some  say  the  heart  Is  a 
voluntary  muscle  because  it  has  striated  fiber-,  but  l1  is  governed  by  the  sym- 
pathetic nerve  thus  making  it  involuntary  in  action. 

The  fibrous  rings  are  stronger  on  the  left  side  than  on  the  right. 


Thev 


244  ANATOMY    IN    A    NUTSHELL. 

surround  the  auriculo-ventricular  openings  and  the  arterial  openings,  giving 
attachment:  to  the  muscle  fibers,  valves,  and  great  vessels. 

The  endocardium  is  a  smooth,  thin  membrane  which  lines  the  heart  and  is 
more  opaque  on  the  left  side  and  is  thickest  in  the  auricles,  being  thicker  in  the 
left  auricle  than  in  the  right, 

Blood  Supply. — The  arteries  are  the  right  and  left  coronary.  The  right 
coronary  artery  arises  from  the  anterior  sinus  of  valsalva  and  passes  forward 
between  the  pulmonary  artery  and  the  auricular  appendix.  From  this  point  it 
runs  in  the  right  auriculo-ventricular  groove  to  the  posterior  interventricular 
groove,  and  here  it  divides  into  a  transverse  branch  which  runs  in  the  left  auricu- 
lo-ventricular groove  and  a  descending  branch  which  runs  in  the  posterior 
interventricular  groove  to  the  apex  of  the  heart.  A  marginal  branch  which 
comes  from  this  artery  runs  along  the  margin  of  the  right  ventricle.  It  also 
gives  infundibular  branches  to  the  right  auricle  and  right  ventricle  and  the  pul- 
monary artery.     (Plate  CXXVIII.) 

The  left  coronary  artery,  which  is  larger  than  the  right,  arises  from  the  left 
posterior  sinus  of  valsalva  and  passes  forward  between  the  pulmonary  artery 
and  the  left  auricular  appendix.  At  this  point  it  divides  into  a  transverse 
branch,  which  runs  outward  in  the  left  auriculo-ventricular  groove  and  a  de- 
scending  branch  which  runs  to  the  apex  of  the  heart  in  the  anterior  interven- 
tricular groove.  The  coronary  arteries  may  come  from  a  common  trunk  and 
there  may  be  one  or  two  small  additional  branches.     (Plate  CXXVII.) 

The  cardiac  veins  return  the  blood  from  the  substance  of  the  heart  into  the 
righl   auricle. 

1.  The  anterior  cardiac  vein,  also  called  great  cardiac  vein,  ascends  from 
the  apex  of  the  heart  to  the  base  of  the  ventricle  in  the  anterior  interventri- 
cular groove.  It  turns  to  the  left  into  the  left  auriculo-ventricular  groove  and 
opens  at  the  back  of  the  heart  into  the  great  coronary  sinus  where  it  has  two 
valves,  it  drains  both  ventricles  (more  the  left  than  the  right),  and  the  left 
auricle. 

2.  The  middle  cardiac  vein  ends  in  the  great  coronary  sinus  after  running 
from  the  apex  of  the  heart  to  its  base  in  the  posterior  interventricular  groove. 

It  has  one  valve  at  its  orifice  and  it  drains  the  posterior  part  of  both  ventri- 
cles. 

:;.  The  posterior  surface  of  the  left  ventricle  is  drained  by  the  left  or  pos- 
terior cardiac  veins  which  empty  into  the  great  coronary  sinus. 

1.  The  right  or  anterior  cardiac  veins  receive  the  blood  from  the  anterior 
surface  of  the  right  ventricle  and  open  separately  into  the  lower  part  of  the 
righl  auricle.  The  largest  one  of  these  veins,  which  runs  along  the  right  border 
of  the  heart,  is  called  the  vein  of  Galen. 

5.  The  right  or  small  coronary  sinus  drains  the  back  part  of  the  right 
auricle  and  right  ventricle  and  it  runs  in  the  right  auriculo-ventricular  groove 
and  end-  in  the  righl  end  of  the  gr<  at  coronary  sinus. 

(').  The  left  or  great  coronary  sinus  is  then  a  portion  of  the  great  cardiac 
vein  which  is  about  an  inch  long  and  occupies  the  posterior  part  of  the  left  auri- 
culo-ventricular groove.     It    receives   the   veins  just    mentioned   and   also   an 


ANATOMY    IX    A    NUTSHELL. 


245 


oblique  vein  from  the  back  of  the  left  auricle  which  is  the  remnant  of  the  obliter- 
ated left  vena  cava  called  duct  of  Cuvier.  This  great  coronary  sinus  ends  in 
the  right  auricle  between  the  inferior  vena  cava  and  the  auriculo-ventricular 
opening.  The  opening  of  this  sinus  is  guarded  by  a  semilunar  fold  of  the  lining 
membrane  of  the  heart  called  the  coronary  valve  or  Thebesii. 

7.  Venae  Thebesii  are  minute  veins  which  drain  the  cardiac  muscular  sub- 
stance and  open  directly  into  the  right  auricle  by  the  foramina  of  Thebesii. 


LESSON  LXVII. 

Nerve  Supply. — The  nerves  to  the  heart  are  derived  from  the  cardiac 
plexuses,  formed  by  the  pneumogastric  and  sympathetic  nerves.  Its  actions 
are  involuntary.     The  nerves  of  the  heart  are  derived  from  three  sources: 

PLATE  XCIX. 


UPPER  INTER- 
VERTEBRAL NOTCH 


SUP.ARTICPROC'S. 
TRANSVERSE 
PROC'S. 


OEMIFACET  FUR  HEAD  OF  RIB. 
LOWER  INTERVERTEBRAL  NOTCH. 


A  Dorsal  Vertebra,  With  Long  Spine. 

1.  From  nerve  cells  buried  in  its  own  substance  and  known  as  the  intrinsic 
ganglia. 

2.  From  the  tenth  pair  (pneumogastric)  of  cranial  nerves. 

3.  From  the  sympathetic  nervous  system. 

The  intrinsic  ganglia  keep  the  heart  beating,  and  the  other  two  sets  of 
nerves  control  the  rate  and  force  of  the  beat. 

Systole  is  contraction  of  the  heart  and  arteries  tor  propelling  the  blood 
and  thus  carrying  on  circulation.     The  expansion  of  the  hearl  is  called  diastole. 

The  heart  has  two  sounds.  The  first  is  longer  in  duration  and  lower  in  pitch 
than  the  second.  It  is  made  by  those  sounds  which  take  place  during  ventri- 
cular systole.     (1)  Muscular  contractions.  (2)  friction  of  blood  rushing  through 


24')  ANATOMY    IN    A    NUTSHELL. 

the  s<  n.ilunar  valves,  (3)  friction  of  the  heart  within  the  pericardium, (4)  fric- 
tion of  heart  against  neighboring  structures.  It  is  of  importance  to  study  the 
norma]  hi  art  sounds  for  any  of  these  four  factors  may  be  modified  by  various 
dis<  ases.  The  second  sound  of  the  heart  is  made  by  those  sounds  which  occur 
during  the  closure  of  the  aortic  semilunar  valves  and  the  pulmonary  semilunar 
valves.  The  position  for  hearing  the  first  sound  is  at  the  apex,  while  the  sec- 
ond sound  is  more  easily  heard  over  the  base  of  the  heart. 

The  tricuspid  and  pulmonary  valves  are  on  a  superficial  plane  to  the  aortic 
and  bicuspid  valves,  thus  a  circle  of  one  inch  in  diameter  includes  a  part  of  all 
the  valves  of  the  healthy  heart.  The  tricuspid  valve  is  situated  behind  the 
median  line  of  the  sternum  between  the  fourth  costo-sternal  articulations.  The 
sound  of  this  valve  is  best  heard  at  the  base  of  the  ensiform  cartilage. 
The  aortic  valve  is  situated  behind  the  left  edge  of  the  sternum  on  a  level  with 
the  lower  border  of  the  third  rib,  and  although  this  valve  is  on  the  left  side  of 
the  heart  we  listen  to  its  sounds  in  the  second  right  or  aortic  interspace 
where  they  are  conveyed.  The  pulmonary  valve  is  situated  behind  the  junc- 
tion of  the  third  costal  cartilage  with  the  sternum, and  although  it  is  situated  on 
the  righl  side  of  the  heart  its  sounds  are  best  heard  in  the  second  left  or 
pulmonary  interspace  where  the  sounds  are  conveyed. 

The  mitral  valve  is  situated  between  the  left  edge  of  the  sternum  and  the 
third  and  fourth  costal  cartilages.  We  listen  at  the  apex  for  this  sound. 
Plate   XVII. 

The  Thyroid  Gland.     (Plates  CXXI-CXXII-CXXXII.) 

There  are  several  organs  in  the  body  that  are  called  ductless  glands  or 
bodies.  They  are  the  thymus  gland,  the  thyroid  gland,  the  spleen,  and  the 
suprarenal  capsules.  Some  anatomists  name  the  additional  organs  as  duct- 
less "lands;  the  tonsils,  the  epiphysis,  the  hypophysis,  the  coccygeal  glands 
and  carotid  glands.  A  gland  is  an  organ  which  secrets  and  pours  forth  fluid  from 
one  or  more  ducts,  and  since  these  bodies  just  named  have  no  ducts  it  would 
seem  that  they  could  not  be  called  glands,  however  they  have  an  internal  se- 
cretion.  The  thyroid  gland  has  a  duct  in  the  fetus  which  leads  to  the  base  of 
the  tongue.  This  gland  is  very  vascular  and  is  situated  upon  the  larynx  and 
upper  part  of  the  trachea.  Although  closely  associated  with  the  trachea,  yet 
it  takes  no  pari  in  respiration.  It  is  the  seat  of  the  disease  known  as  bron- 
chocele  or  goiter.     The  following  are  the  main  forms  of  goiter: 

1.  Exophthalmic  (Grave's  disease.)  Where  there  is  a  great  vascularity 
and   often    pulsation,    accompanied    by   exophthalmus,  palpitation,  and  rapid 

pulse. 

2.  Fibroid.     Where  there  is  an  increase  of  the  interstitial  tissue. 

3.  Cystic.  Where  there  are  one  or  more  cysts  formed  from  dilatation 
and   possibly  coalescence  of  adjacent   follicles. 

4.  Pulsating.     Where  vascular  changes  predominate. 
.").   Parenchymatous.     Where  the  follicles  are  enlarged. 

This  gland  consists  of  two  lobes,  which  are  pyriform  in  shape,  and  an 
isthmus.     The  dimensions  of  the  lobes  are  two  inches  in  length,  three-quarters 


ANATOMY    IX    A    NUTSHELL. 


247 


of  an  inch  in  thickness,  and  an  inch  and  a  quarter  in  breadth.  It  extends  from 
the  middle  of  the  thyroid  cartilage  to  the  sixth  ring  of  the  trachea,  and  the 
isthmus  crosses  the  trachea  about  the  third  ring.  The  isthmus  may.  in  rare 
cases,  pass  behind  the  trachea  in  front  of  the  oesophagus.  This  gland  weighs 
from  one  to  two  ounces.  It  is  larger  in  the  female  and  is  increased  in  size  dur- 
ing menstruation. 

Blood  Supply. — The  superior  thyroid  arteries,  which  are  branches  of  the 
external  carotid,  supply  the  apex  and  inner  and  fore  parts  of  the  lateral  lobes. 
The  inferior  thyroid  arteries,  which  come  from  the  thyroid  axis,  supply  the 

PLATE  C. 


A  Lumbar  Vertebra. 


outer  and  posterior  portion  of  the  lateral  lobes.  The  thyroidea  ima.  which  is 
derived  either  from  the  innominate  artery  or  from  the  arch  of  the  anna,  ascends 
on  the  front  of  the  trachea  to  anastomose  with  the  superior  and  inferior  thy- 
roid arteries  and  helps  to  supply  the  isthmus.  The  veins  arc  the  superior 
thyroid  which  empties  into  the  internal  jugular,  and  the  middle  thyroid  which 
empties  into  the  same,  and  the  inferior  thyroid  which  empties  into  the  innom- 
inate of  the  corresponding  side. 

Nerve  Supply. — From  the  superior  and  middle  cervical  ganglion  of  the 
sympathetic,  and  possibly  a  branch  from  the  tenth. 

A  goiter  may  be  distinguished  from  a  cervical  tumor  by  the  fact  thai  it 
rises  ami  falls  on  deglutition. 


248  ANATOMY    IN    A    NUTSHELL. 

The  Spleen.     (Plate  CXLVI1.) 

The  dimensions  of  the  spleen  are  one  by  three  by  five  inches,  and  it  weighs 
aboul  five  ounces.  It  consists  of  an  external  portion  called  cortex,  and  an  in- 
ternal portion  called  the  medullary  portion.  This  internal  portion  consists  of 
a  honey-combed  arrangement  and  in  these  cells  are  the  MaJpighian  corpuscles 
•which  arc  about  one-twenty-fifth  of  an  inch  in  diameter.  The  spleen  manu- 
factures white  blood  corpuscles  and  has  no  true  set  of  capillaries,  the  blood 
emptying  into  these  spaces  from  which  it  is  collected  into  the  veins.  There 
may  be  numerous  accessory  spleens.  The  spleen  has  no  excretory  duct  and 
therefore  no  proper  secretion.  The  Ancients  thought  the  spleen  to  be  the  seat 
of  various  emotions.     It  is  situated  in  the  left  hypochondriac  region. 

The  relations  of  the  spleen  are  as  follows: 

In  Front. — Stomach  and  splenic  flexor  of  colon. 

Behind. — The  Diaphragm. 

Outer  Side. — Diaphragm,  ninth  to  eleventh  ribs  between  the  axillary  line. 

Inner  Side. — Stomach,  pancreas,  left  kidney,  and  suprarenal  capsule. 

Blood  Supply. — The  splenic  artery,  which  is  a  branch  of  the  cceliac 
axis,  divides  before  entering  the  spleen  into  about  six  branches.  This  artery 
is  tortuous  and  large  in  porpotion  to  the  body  it  supplies.  The  spleen  is  en- 
tirely covered  by  peritoneum  beneath  which  there  is  a  plexus  of  lymphatic 
vessels.  The  lymphatics  of  the  spleen  are  divided  into  a  superficial  and  a  deep 
set.  The  veins  of  the  spleen  form  one  main  vein  called  the  splenic  which  empties 
into  the  portal  vein. 

Nerve  Supply. — The  splenic  plexus  which  comes  from  the  solar  plexus 
and  passes  along  the  splenic  artery. 


LESSON  LXVIII. 

The  Thymus  Gland.     (Plate  CXXXII.) 

This  gland  is  situated  within  the  thorax  behind  the  sternum  near  the  neck. 
It  is  a  fetal  structure  and  begins  to  disappear  about  the  second  year  after  birth. 
The  thymus  gland  of  the  sheep  is  called  throat, or  neck, sweet  bread  to  distin- 
guish it  from  the  pancreas, or  stomach  sweet  breath  This  gland  reaches  its 
highest  development  about  the  second  year  and  its  weight  it  is  six  drachms. 

Blood  Supply. — Internal  mammary,  superior  and  inferior  thyroid.  The 
veins  empty  into  the  left  innominate  vein  and  thyroid  veins. 

Nerve  Supply.     Sympathetic  and  pneumogastric. 

Suprarenal  Capsules.     (Adrenal  Bodies.)      (Plate  CXLVII.) 

These  bodies  are  solid  viscera  situated  on  the  upper  extremity  of  each  kid- 
ney. They  are  richly  supplied  with  vessels  and  nerves.  Dimensions  are  two 
inches  by  one-half  by  one-half.  Weight  is  one  drachm.  They  are  not  in- 
vested  by  peritoneum. 

Blood  Supply.  Suprarenal,  phrenic,  and  renal  arteries,  which  pierce  the 
organs  chiefly  on  the  anterior  surface  along  a  furrow  called  the  hilum.  The 
veins  empty  on  the  rigb.1  side  into  the  vena  cava  and  occasionally  by  means  of 


ANATOMY    IN    A    NUTSHELL. 


249 


small  branches  into  the  phrenic  and  renal  veins.  Those  on  the  left  side  empty 
into  the  renal  vein.  The  lymphatics  of  this  organ  pass  into  the  renal  glands. 
The  renal  glands,  as  well  as  the  suprarenal  capsule,  contain  a  good  deal  of  pig- 
ment. 

Nerve  Supply. — Solar  and  renal  plexuses,  and  possibly  the  splanchnic, 
phrenic,  and  the  pneumogastric  nerves. 

The  other  ductless  glands  mentioned  will  be  described  in  their  proper 
places. 

PLATE  CI. 

DORSI-SPINAL  VEINS 


INTERCOSTAL    VEI 


ANTERIOR  LONGITUDINAL 
MENINGO-RACHIDIAN. 


INTERCOSTAL     VEIN 


VENAE     BASIS  VERTEBRARUM. 


Veins  of  Spinal  Cord  and  Column  (Transverse  View.) 
Larynx.     (Plate  CXXIL) 

The  larynx  (the  organ  of  phonation)  is  thai  part  of  the  trachea  in  which 
vocal  sound  is  made  and  modulated.  It  is  the  upper  end  of  the  trachea  which  is 
enlarged  and  modified.  It  opens  by  the  glottis  into  (he  pharynx  and  is  con- 
tinuous below  with  the  trachea.  The  larynx  is  larger  in  men  than  in  women 
by  about  one-third.  In  some  animals  the  larynx  may  be  situated  any  where 
along  the  wind  pipe  or  even  in  the  bronchial  tubes.  In  birds  there  are  two 
larynges,  one  at  the  top  of  the  trachea  ami  the  other,  at  the  bottom  of  the 
trachea,  which  is  called  syrinx.  The  opening  of  the  trachea  is  called  the  glottis. 
The   word   glottis   is   sometimes   applied    to    this   opening   with    the   contiguous 


250  ANATOMY    IN    A    NUTSHELL. 

structures  as  one  mighl  say  oedema  of  the  glottis  just  as  he  would  say  mouth  to 
include  the  lips.  The  anterior  part  of  the  glottis  is  called  glottis  vocalis  and  is 
hounded  by  the  true  vocal  cords,  while  the  posterior  part  is  called  glottis  res- 
piratoria  and  is  hounded  by  the  internal  margins  of  the  arytenoid  cartilages. 

The  epiglottis  (Plates  CXXII-CXXXIV-CXXXV-CXXXVI-CXXXVIL) 
i>  a  valve-like  organ  which  prevents  the  food  from  entering  into  the  glottis  during 
deglutition.  The  superior  or  false  vocal  cords  are  two  folds  of  mucous  mem- 
Inane  which  enclose  a  delicate  rounded  hand,  the  superior  thyro-arytenoid 
ligament.  They  are  called  false  vocal  cords  because  they  are  not  directly  con- 
cerned  in  the  production  of  the  voice.  The  inferior  or  true  vocal  cords  are  two 
strong  fibrous  bands,  inferior  thyrc-arytenoid  ligament,  which  are  covered  by 
a  thin  layer  of  mucous  membrane.  They  are  called  true  vocal  cords  because 
they  are  concerned  in  the  production  of  the  voice. 

The  sinus  of  the  larynx,  (Plate  CXXXVII)  which  is  situated  between  the 
false  and  true  vocal  cords  on  each  side,  leads  into  the  sacculus  laryngis  (sinus 
Morgagni.)  There  are  nine  cartilages  of  the  larynx,  three  of  which  are  single 
and  three  are  in  pairs.  The  single  ones  are  (1)  epiglottis,  (2)  thyroid,  (3)  cri- 
coid. (Plate  CXXXVI.)  Those  in  paris  are  (1)  the  two  arytenoid,  (2)  two 
cornicula  laryngis,  and  (3)  the  two  cuneiform,  The  cricoid  and  thyroid  and 
the  arytenoid  (excepting  tin  tip)  are  hyaline  in  structure.  The  tip  of  the 
arytenoid,  the  epiglottis,  the  cornicula  laryngis,  and  the  cuneiform  are  yellow 
elastic.  The  ligaments  of  the  larynx  are  arranged  in  two  sets,  the  extrinsic 
which  are  three  in  number,  connect  the  larynx  to  the  hyoid  bone,  and  the  in- 
trinsic, which  are  sixteen  in  number,  connect  the  cartilages  of  the  larynx  to  one 
another. 

The  extrinsic  ones  are: 

Thyro-hyoid  membrane.     (Plate  CXXXIV.) 

Two  lateral  thyro-hyoid  ligaments,  each  of  which  contains  a  nodule  cartil- 
age, (the  cartilage  triticea.) 

The  sixteen  intrinsic  ligaments  are: 

Crico-  thyroid  membrane.      (Plate  CXXXIV.) 

Two  crico-thyroid  capsular  ligaments. 

Two  crico-arytenoid  ligaments. 

Two  crico-arytenoid  capsular  ligaments. 

Two  superior  thyro-arytenoid  (situated  in  the  false  vocal  cords.) 

Two  inferior  thyro-arytenoid  (situated  in  the  true  vocal  cords.) 

Hyo-epiglottic  ligament. 

Thyro-epiglottic  ligament. 

Three  glosso-epiglottic  folds. 

The  muscles  of  the  larynx  are  as  follows;  (1)  Crico-thyroid,  (2)  Crico- 
arytenoideus  posticus.  (3)  Crico-arytenoideus  lateralis,  (4)  Thyro-aryte- 
Doideus  (5)  Arytenoideus,  (6)  Thyro-epiglottideus,  (7)  Aryteno  epiglottideus 
superior.  (8)  Aryteno-epiglottideus  inferior.  All  these  muscles  are  in  pairs 
excepi  the  Arytenoideus,  which  is  a  single  muscle.  Three  of  these  muscles  be- 
long to  the  epiglottis.     (Plate  CXXXVI.) 


ANATOMY    IN    A    NUTSHELL. 


251 


LESSON  LXIX. 
Cricothyroid  Muscle. 

Origin. — From  the  side  of  the  cricoid  cartilage. 

Insertion. — Into  the  interior  border  and  lower  cornu  of  thyroid  cartil 
age. 

Action. — Rotates  the  posterior  part  of  cricoid  cartilage  downward  and 
backward,  and  thus  tightens  the  vocal  cords. 

Nerve  Supply. — External  laryngeal  from  the  superior  laryngeal. 

Blood  Supply. — The  superior  laryngeal  from  the  superior  thyroid,  and 
the  inferior  larvngeal  from  the  inferior  thyroid.     The  veins  have  the  same  name 


PLATE  CTI. 


ANTERIOR  LONGITUDINAL 
WENINGO-RACHIDIAN. 


POSTERIOR    LONGITUDINAL. 
YENINCO-RACHIDIAN 


VENAE      BASIS  VERTEBRARUM 


Veins  of  Spinal  Cord  axd  Column  (Sagittal  View.) 

as  the  arteries  and  accompany  them.     This  is  the  blood  supply  of  all  the  mus- 
cles of  the  larynx. 

Crico-arytenoideus  Posticus. 

Origin. — From  posterior  surface  of  the  cricoid  cartilage. 

Insertion. — Into  the  outer  angle  of  the  base  of   the   arytenoid   cartilage. 

Action. — It  dilates  the  glottis  bv   rotating  the  arytenoid  cartilage  out- 


ward. 


Nerve  Supply'. — Recurrent  laryngeal  from  the  pneumogastric  nerve. 
Crico-arytenoideus  Lateralis. 

Origin. — From  the  upper  border  of  the  sides  of  the  cricoid  cartilage. 


252  ANATOMY    IN    A    NUTSHELL. 

Insertion. — Into  the  external  angle  of  the  base  of  the  arytenoid  cartilage 
in  front  of  the  Crico-arytenoideus  posticus. 

Action. — T<>  contract  the  glottis  by  rotating  the  arytenoid  cartilage  in- 
ward. 

\i  i;\  e  Supply. — Recurrent  laryngeal  from  the  pneumogastric. 

Thyro  -arytenoideus. 

Origin. — From  the  side  of  the  angle  of  the  thyroid  cartilage  and  the  crico- 
thyroid  membrane. 

[nsertion.-  Into  the  anterior  surface  and  base  of  the  arytenoid  cartilage. 

Action. — Relaxes  the  vocal  cords  by  drawing  the  arytenoid  cartilage  for- 
ward. 

Nerve  Supply. — Recurrent  laryngeal  from  the  pneumogastric. 

Arytenoideus  Muscle. 

Origin. — This  is  the  single  muscle  of  the  larynx  and  comes  from  the  pos- 
terior surface  of  the  arytenoid  cartilage,  its  fillers  running  in  a  transverse  direc- 
tion pass  from  one  cartilage  to  the  other. 

Insertion. — Into  the  posterior  surface  of  the  arytenoid  cartilage. 

Action. — It  assists  in  contracting  the  glottis  by  approximating  the  aryten- 
noid  cartilages. 

Nerve  Supply. — Recurrent  laryngeal  from  the  pneumogastric,  and  the 
superior  laryngeal. 

Thyro-Epiglottideus. 

Origin. — From  the  angle  of  the  thyroid  cartilage  just  above  the  Thyro- 
arytenoideus. 

Insertion. — Into  the  lower  border  of  the  epiglottis  and  into  the  aryteno- 
epiglottic  fold. 

Action. — To  compress  the  sacculus  laryngis  and  to  depress  the  epiglottis. 

Nerve  Supply. — Recurrent  laryngeal  nerve. 

Aryteno-Epiglottideus  Superior. 

Origin. — From  the  tip  of  the  arytenoid  cartilage. 

[nsertion.  Into  the  mucous  membrane  attached  to  the  side  of  the  epi- 
glottic 

Action. — Contracts  the  superior  opening  of  the  larynx. 
Nerve  Supply. — Recurrent  laryngeal. 

Aryteno-Epiglottideus  Inferior. 

Origin. — From  the  anterior  surface  of  the  arytenoid  cartilage. 

[nsertion.— Into  the  upper  and  inner  part  of  the  epiglottis.  This  muscle 
is  separated  from  the  superior  muscle  by  a  distinct  interval.  It  is  often  called 
the  Compressor  sacculus  laryngis  of  Hilton.  The  Triticeo-glottis  muscle  is  a 
small  muscle  which  is  frequently  present.  Its  origin  is  from  the  corpus  tri- 
ticeuni,  and  after  passing  forward  and  upward  to  join  the  Cerato-glossus, it  is 
inserted  into  the  tongue. 


PLATE  CIII. 


m> 


VC. 


;,  4n 


Ttf? 


The  Spinal  Column. 
253 


254  ANATOMY    IN    A    NUTSHELL. 

A<  tii  in. -  Contracts  the  superior  opening  of  the  larynx. 

Nerve  Supply. — Recurrent  laryngeal  nerve. 

Nerve  Supply. — The  Crico-thyroid  muscles  and  mucous  membrane  of  the 
larynx  receive  the  superior  laryngeal  nerves,  all  the  remaining  muscles  receive 
the  inferior  <>r  recurrent  laryngeal  nerves.  The  Arytenoideus  receives  both 
superior  and  inferior  laryngeal  nerves. 

1  ;;.oi  in  Supply.  The  laryngeal  branches  from  the  superior  thyroid  and 
inferior  thyroid  arteries  pass  to  the  larynx.  The  veins,  which  accompany  the 
superior  laryngeal  artery,  join  the  superior  thyroid  vein  which  empties  into  the 
internal  jugular  vein.  The  veins  which  accompany  the  inferior  laryngeal 
artery  join  the  interior  thyroid  vein  which  empties  into  the  innominate  vein. 
The  lymphatics  pass  into  the  deep  cervical  nodes. 

Trachea.     (Plate  CXX.) 

The  word  trachea  comes  from  a  Greek  word  which  means  rough.  It  is  also 
called  the  wind  pipe  and  is  the  air  passage  of  the  body  beginning  at  the  larynx 
and  ending  in  the  bronchial  tubes.  It  is  composed  of  sixteen  to  twenty  car- 
tilages or  osseous  rings.  The  first  ring  is  called  the  cricoid  cartilage,  and  the 
last  one  is  called  the  pessulus.  This  last  one  is  situated  at  the  forking  of  the 
trachea  into  the  right  and  left  bronchial  tubes.  The  trachea  is  a  musculo- 
membranous  tube  and  it  communicates  with  the  mouth  and  nose  through  the 
larynx,  and  with  the  lungs  through  the  bronchial  tubes.  All  vertebrates, which 
breathe  air  with  lungs,  have  a  trachea  which  is  subject  to  very  little  variation 
in  character.  The  human  trachea  is  about  four  and  one-half  inches  long,  ex- 
tending from  the  sixth  cervical  vertebra  to  the  fourth  dorsal  vertebra  where  it 
branches  into  the  two  bronchi.  The  oesophagus  is  between  the  trachea  and  the 
spinal  column.  The  average  diameter  of  the  trachea  is  about  four-fifths  of  an 
inch  in  the  cadaver.  The  antero-posterior  diameter  is  somewhat  less.  Dur- 
ing  life  these  dimensions  are  smaller.  The  rings  of  the  trachea  are  incomplete 
behind  where  they  join  the  (esophagus. 

Blood  Supply.  —Inferior  thyroid  arteries.  The  veins  terminate  in  the 
thyroid  venous  plexus. 

Nerve  Supply.— Pneumogastric  and  sympathetic. 

The  right  bronchus  is  about  an  inch  in  length  and  in  direction  is  more  hor- 
izontal in  its  passage  to  the  rool  of  the  lung  than  the  left  bronchus.  It  is  wider 
than  lie  Nft  and  divi  les  into  three  branches  to  the  lung.  The  left  bronchus 
is  nearly  tun  inches  in  length  and  is  smaller,  longer,  and  more  oblique  than  the 
righl  one.  It  enters  the  root  of  the  lung  opposite  the  sixth  dorsal  vertebra, 
which  is  alioiii  an  inch  lower  than  the  point  whe'e  the  right  bronchus  enters 
i In  lung.  It  divides  into  two  branches.  It  has  above  it  the  arch  of  the  aorta. 
behind  it  the  (esophagus,  thoracic  duct,  and  the  descending  aorta.  The  left 
pulmonary  artery  is  a1  first  above,  then  in  front  of  the  left  bronchus. 


LESSON  LXX. 

Lungs.     (Plates  CXXI-CXXII-CXXIII.) 
Tin    word  Lung  comes  from   the   Latin   pulmones,  from  which  comes  pul- 


ANATOMY    IX    A    NUTSHELL. 


255 


monary.  The  lungs  are  two  large  organs  which  occupy  a  great  part  of  the  chest 
cavity.  The  heart,  oesophagus,  and  the  great  vessels  separate  them.  They 
are  the  organs  of  respiration  in  air  breathing  vertebrates  and  communicate 
with  the  pharynx  through  the  trachea.  The  air  cells  (alveoli)  are  from  one 
fiftieth  to  one-seventieth  of  an  inch  in  diameter.  The  lungs  are  formed  by  re- 
peated subdivisions  of  the  bronchial  tubes  which  finally  end  in  saccular  dilata- 
tions called  infundibula.     The  air  cells  are  in  the  infundibula  and  the  air  pass- 


UPPER  FASCICULUS 
MIDDLE  FASCICULUS. 
.OWER  FASCICULUS. 


PLATE  CIV. 


_-*->  THREE  SLIPS  OF  THE  STELLATE  LIGAMENT 

ANTERIOR  COSTOVERTEBRAL  LIGAMENT 


ANTERIOR  OR  SUPERIOR  COSTOTRANSVERSE  LIGAMENT 

Ligaments  of  Spinal  Column. 

ages  leading  to  them.  These  cells  have  a  capillary  net-work  in  which  the 
branches  of  the  pulmonary  art<  ry  <  nd  and  In  re  the  blood  is  s<  parat<  d  from  the 
air  by  the  capillary  wall  and  the  thin  alveolar  epithelium  of  the  air  cells.  The 
lung  is  comparatively  compact,  being  composed  of  air  breathing  tubes  bound 
tip  by  connective  tissue. 

Blood  Supply. — From  the  bronchial  arteries  which  vary  in  number,  size. 
and  origin.  The  one  on  the  right  side  may  conic  from  (1)  the  first  aortic  in- 
tercostal. (2)  by  a  common  trunk  with  the  lefl  bronchial  from  the  f I  of  the 

thoracic  aorta.  On  the  left  side  ther<  are  generally  two  which  conic  from  the 
thoracic  aorta.     The  bronchial  veins  do  not  return  all  the  blood  carried  to  the 


256  ANATOMY    IN    A    NUTSHELL. 

lungs  by  the  bronchial  arteries,  for  that  part  which  is  distributed  to  the  smaller 
bronchial  tubes  and  alveolae  is  brought  back  by  the  pulmonary  veins.  The 
right  bronchial  vein  empties  into  the  vena  azygos  major  just  before  that  vein 
empties  into  the  superior  vena  cava.  The  left  bronchial  vein  empties  into  the 
lower  left  superior  intercostal  vein  or  into  the  vena  azygos  tertius.  Small 
veins  from  the  bronchial  glands,  from  the  trachea,  and  from  the  posterior  med- 
iastinum empty  into  the  bronchial  veins  at  the  root  of  the  lung.  The  lymphatics 
of  the  lungs  are  numerous. 

The  base  of  each  lung  rests  upon  the  Diaphragm  and  its  apex  passes  through 
the  superior  opening  of  the  thorax  about  an  inch  above  the  clavicle.  Each 
lung  is  pyramidal  in  form  and  the  right  one  is  divided  into  an  upper  lobe,  a 
middle  lobe,  and  a  lower  lobe,  while  the  left  lung  is  divided  into  an  upper  lobe 
and  a  lower  lobe.  The  root  of  each  lung  is  little  above  the  middle  at  the  inner 
side  and  except  for  this  attachment  the  lung  lies  free  in  the  pleural  cavity  which 
it  completely  fills.  The  lung  is  elastic  and  always  on  a  tension.  The  blood  in 
passing  through  the  lungs  gives  off  carbon  dioxide  to  the  air  in  the  alveolae  and 
receives  oxygen.  This  process  which  takes  place  in  the  lung  is  a  simple  physical 
change  and  has  nothing  to  do  with  any  secreting  or  other  activity  of  the  epi- 
thelial cells. 

Nerve  Supply. — It  is  from  the  anterior  and  posterior  pulmonary  plexuses, 
which  are  formed  from  the  sympathetic  and  pneumogastric.  Filaments  from 
these  plexuses  accompany  the  bronchial  tubes  upon  which  they  are  lost.  Small 
ganglia  are  formed  upon  these  nerves. 

The  right  lung  (Plates  CXXI-CXXII-CXXIII.)  weighs  twenty-two  ounces 
and  the  left  one  twenty.  Their  capacity  is  nearly  seven  and  a  half  pints.  The 
entire  respiratory  surface  is  more  than  eight  hundred  and  seventy  square  feet. 
At  birth  the  lungs  are  a  reddish  brown  and  change  to  a  rose  pink  on  inflation. 
They  are  grayish  white  in  adult  life  and  brownish  in  middle  life  and  bluish 
black  in  old  age.  The  specific  gravity  varies  from  345  to  746,  water  being  1000. 
The  serous  membrane  which  covers  the  lung  is  the  pleura .  (Plates  CXXY-CXXVL) 
Each  pleura  is  an  inclosed  sac  and  they  do  not  touch  each  other.  Each  has  a 
parietal  layer  called  a  costal,  and  a  visceral  layer  called  pulmonary.  The 
movements  of  the  lungs  in  the  chest  are  facilitated  by  serous  secretion  in  the 
pleura.     The  parietal  pleura  has  different  names  for  its  various  portions. 

1.  Tin-:  costal  pleura  is  that  which  lines  the  ribs,  costal  cartilages,  and 
intermediate  muscles. 

2.  The  diaphragm  \tic  pleura  is  that  which  is  attached  to  the  Diaphragm. 

3.  The  mediastinal  pleura  is  that  which  is  attached  to  the  adjacent 
structures  in  the  mediastinum. 

4.  The  <  i;k\  ecal  pleura  is  that  which  covers  the  dome  of  the  lung. 
Blood  Supply. — Internal  mammary,  intercostal,  musculo-phrenic,  thymic, 

pericardiac,  bronchial.  The  veins  correspond  to  the  arteries.  The  lymphatics 
are  numerous. 

Nerve   Supply. — Sympathetic   and    phrenic. 

The  broad  ligamenl  of  the  lung  is  a  fold  of  the  visceral  layer  of  the  pleura 
which  after  covering  the  root  of  the  lung  comes  together  directly  beneath  it 


ANATOMY    IX    A  NUTSHELL. 


257 


forming  a  triangular  sheet,  passing  vertically  from  the  root  of  the  lung  to  the 
Diaphragm,  and  laterally  from  the  lung  to  the  mediastinal  pleura. 

The  root  of  the  lung  is  composed  of  (1)  the  pulmonary  artery,  (2)  pulmonary 
veins,  (3)  bronchial  tube,  (4)  bronchial  vessels,  (5)   anterior  pulmonary  plexus, 

PLATE  CV. 


ANTERIOR  TUBERCLE    OF    ATLAS    TO    WHICH   THE  LONGU  COLLI    IS    INSERTED 


THE    ORIGIN  OF 

THE  UPPER  OBLIQUE 

PORTION  OFLONGUS  COLLI 


INSERTION  OF  INFERIOR 
OBLIQUE  PORTION 
OF  LONGUS  COLLI 


RECTUS  CAPITIS    ANTICUS 
MINOR        ORIGIN 


THIS  AND  THE  THREE  SUCCEEDING 

PROCESSES  GIVE  ORIGIN  TO  THE 
RECTUS  CAPITIS    ANTICUS  MAJOR 
AND     THE  SCALENUS  ANTICUS 


ORIGIN  OF  VERTICAL  PORTION  OF  THE  LONGUS  COLLI.    ITS  INSERTION  IS 
INTO  THE  SECOND.  THIRD  AND  FOURTH  VERTEBRAE 

Anterior  View  of  Cervical  Vertebra. 

(6)  posterior  pulmonary  plexus,  (7)  bronchial  lymphatic  nodes,  (8)  areola! 
tissue.  All  these  are  enclosed  in  the  pleural  covering.  The  first  three  of  these 
are  the  main  structures  in  the  root  of  the  lung  and  bear  the  following  relations 
from  before  backward  in  each  lung:  Vein,  artery,  and  bronchus.  From  above 
down  in  the  left  root  we  have  artery,  bronchus,  and  vein.  In  the  righl  one 
from  above  down  we  have  bronchus,  artery  and  vein. 

Relations  of  the  root  of  the  right  lung.     (Plate  CXXVII.) 


258  ANATOMY    IN    A    NUTSHELL. 

In  Front. — (1)  .Superior  vena  cava.  (2)  upper  portion  of  right  auricle  of 
heart.  (3)   anterior  pulmonary  plexus,  (4)  right  phrenic  nerve. 

Behind. — (1)  Posterior  pulmonary  plexus,  (2)  pneumogastric  nerve,  (3) 
vena  azygos  major. 

Above. — (1)   Vena  azygos  major. 

Below. — Broad  ligament    (ligamentum  latum  pulmonis.) 

Relations  of  the  left  root.     (Plate  CXXVIL) 

In  Front. — (1)  The  anterior  pulmonary  plexus. (2)  the  left  phrenic  nerve. 

Behind. — The  descending  aorta,  (2)  pneumogastric  nerve,  (3)  posterior 
pulmonary  plexus. 

Above. — The  arch  of  the  aorta. 

Below. — The  broad  ligament  (ligamentum  latum  pulmonis.) 

About  one  hundred  cubic  inches  of  air  remains  in  the  lungs  which  cannot 
be  expelled.  (Plate  CXXIY.)  This  is  called  residual  air.  After  an  ordinary 
expiration  one  hundred  cubic  inches  of  air  can  be  expelled  by  forced  expira- 
tion, this  is  called  reserve  air.  About  twenty  or  thirty  cubic  inches  of  air  which 
passes  in  and  out  during  the  ordinary  breathing  is  called  tidal  air.  After  an 
ordinary  inspiration  one  can  inhale  one  hundred  and  twenty  cubic  inches  of  air, 
which  is  called  eomplemental  air.  After  the  complemental  air  has  been  taken 
into  the  lungs  then  one  may  expell  all  the  air,  except  the  residual  air,  and  this 
is  called  vital  capacity. 


LESSON  LXXI. 

A  vertebra  (Plate  XC1X)  consists  of  a  body  and  an  arch,  the  latter  being 
formed  by  two  pedicles  ami  two  laminae  which  support  the  seven  processes. 
The  body  is  thick  and  spongy,  convex  in  front  from  side  to  side  and  concave 
vertically  on  the  upper  and  lower  surfaces  which  are  surrounded  by  bony  rims. 
Anteriorly  are  small  foramina  for  nutrient  vessels,  posteriorly  a  large  foramen 
for  the  exit  of  the  venae  basis  vertebrarum.  The  pedicles  project  backward  from 
the  body,  inclining  outward;  they  are  noticed  above  and  below,  thus  forming, 
with  the  adjacent  notches,  the  intervertebral  foramina  for  the  entrance  of  ves- 
sels  and  the  exit  of  spinal  nerves.  The  laminae  are  two  broad  plates  meeting 
in  the  spinous  process  belaud  and  rough  on  the  upper  and  lower  borders  for  the 
attachment  of  the  ligamenta  subfiava.  The  transverse  processes,  one  on  each 
vide,  project  outward.  The  articular  processes,  two  on  each  side,  superior  and 
inferior,  project  from  the  junction  of  the  lamina?  and  the  pedicles,  articulating 
above  and  below  with  the  articular  processes  of  the  adjacent  vertebrae.  Their 
superior  facets  look  upward  in  the  cervical  region,  outward  in  the  dorsal  region, 
and  inward  in  the  lumbar.  The  spinous  process  projects  backward  from  the 
junction  of  the  lamina?,  sometimes  very  obliquely.  The  spinal  foramen  is  the 
-pace  enclosed  by  the  body,  pedicles, and  lamina?,  and  each  foramen  when  the 
vertebrae  are  articulated,  form  part  of  the  spinal  canal. 

There  are  thirty-three  vertebra?  in  number,  exclusive  of  those  which  form 
the  skull,  having  received  the  names  of  cervical,  dorsal,  lumbar,  sacral,  and 
coccygeal,  according  to  the  position  which  they  occupy,  seven  being  found  in 


ANATOMY    IN    A    NUTSHELL. 


259 


the  cervical  region,  twelve  in  the  dorsal,  five  in  the  lumbar,  five  in  the  sacral, 
and  four  in  the  coccygeal.  (Plate  CIII.)  Their  number  is  sometimes  increased 
by  an  additional  vertebra  in  one  region,  or  the  number  may  be  diminished  in 
one  region,  the  deficiency  being  supplied  by  an  additional  vertebra  in  another. 
These  observations  do  not  apply  to  the  cervical  portion  of  the  spine,  the  number 

PLATE  CVI. 

RECTUS  CAPITIS  POSTICUS  MINOR 


TRANSVERSE  PROCESS  OF  ATLAS 


LEVATOR  ANGULI  SCAPULAE 
ORIGIN 


SPLENIUS  COLLI 
.INSERTION 


LEVATOR  ANGULI  SCAPULAE 
SPLENIC  COLLI 
SCALENUS  MEDIUS  .INSERTION 

LEVATOR  ANGULI  SCAPULAE 
SPlfNIUS  COLLI 
SCALENUS  MEDIUS 

COMPLEXUS 

LEVATOR  ANGULI  SCAPULAE 
SPLENIUS  COLLI 
■SOMETIMES 
SCALENUS  MEDIUS 

COMPLEXUS  AND 
MULTIFIDUS  SPINAE 

SCALENUS  MEDIUS 
SCALENUS  POSTICUS 
COMPLEXUS  AND  TRACHELO 
MASTOID.  MULTIFIDUS  SPINAE 

SCALENUS  MEDIUS 
SCALENUS  POSTICUS 
COMPLEXUS  AND  TRACHELO- 
MASTOID.  MULTIFIDUS  SPINAE 

SCALENUS  MEDIUS 

SCALENUS  POSTICUS j&j£*    ' ,' 

COMPLEXUS  AND  TRACHELO- 
MASTOID.  MULTIFIDUS  SPINAE 


MULTIFIDUS  SPINAE 
lAND  TO  EACH  SPINOUS  PROCESS  AS  HIGH  AS  THE  SECOND 


RECTUS  CAPITIS  LATERALIS 

SUPERIOR  OBLIQUE 
-  INFERIOR  OBLIQUE 


RECTUS  CAPITIS  POSTICUS  MAJOR 

THE  POINTER  CROSSES  THE  ORIGIN 

OF  THE  INFERIOR  OBLIQUE 

SEMISPINALS  COLLI 
CERVICAUS  TRANSVERSUS 


SEMISPINALS  COLLI 


CERVICAUS  TRANSVERSUS 
CERVICAUS  ASCENDENS 


SEMISPINALS  COLLI 

CERVICAUS  ASCENDENS 

CERVICAUS  TRANSVERSUS 


CERVICAUS  TRANSVERSUS 
CERViCALiS  ASCE\0ENS 


-  3  COLLI 


LEVATOR  COSTAE    ORIGIN 
ACCESSORIUS    INSERTION 


INTERSPINALES 


TRAPEZIUS.    RHOMBOIDEUS    MINOR.    SERRATUS 
POSTICUS     SUPERIOR.       SPLENIUS.      COMPLEXUS 


Postekiob  View  uf  Cervical  Vertebrae. 

of  bones  forming  which  is  seldom  incr<  ased  or  diminished. 

The  peculiar  vertebra'  are  the  first  cervical  or  atlas,  SE<  OND  CERVU  al 
or  AXIS,  and  THE  SEVENTH   CERVICAL  Or  VERTEBRA    PROMINENS.       (Plates   XCV- 

XCVI-XCVII.)     The  great  modifications  in  the  form  of  the  atlas  and  axis  arc 
d(  signed  to  admit  of  nodding  and  rotary  movements  of  the  head. 

The  peculiar  vertebra*  in  the  dorsal  region  are  the  first,  ninth,  tenth, 
Eleventh,  and  twelfth.     (Plate  CVII.)     In  the  lumbar  region  the  fifth  is 


260  ANATOMY    IN    A    NUTSHELL. 

peculiar.  The  peculiarity  of  the  first  dorsal  is  that  it  has  one  facet  and  a  demi- 
facet.  The  ninth  dorsal  has  a  demi-facet  only.  The  tenth  has  but  one  facet 
mi  its  body  and  one  on  the  transverse  process.  The  eleventh  and  twelfth  have 
each  but  one  facet  on  the  body,  and  none  on  the  transverse  process.  The 
twelfth  resembles  a  lumbar  vertebra  in  size  and  shape.  The  fifth  lumbar  is  much 
deeper  in  front  than  behind.  Its  spinous  process  is  small,  but  its  transverse 
processes  are  large  and  thick  and  point  slightly  upward. 

The  atlas  has  ten  pairs  of  muscles  attached  to  it. 
I'm  anterior  arch.       Longus  Colli.  1  Ant.  vertebral  region. 

To  posterior  arch.     Rectus  capitis  posticus  minor.     2  Fifth  layer  of  back. 

Rectus  capitis  anticus  minor.  3  Ant.  vertebral  region. 
Rectus  capitis  lateralis.  4  Ant.  vertebral  region. 
Inferior  oblique.  5  Fifth  layer  of  back. 
To  transverse  pro-    Superior  oblique.  6  Fifth  layer  of  back, 
cess.                        Splenius  colli.  7  Third  layer  of  back. 
Levator  anguli  scapula?.  8  Second  layer  of  back- 
Anterior  intertransversalis.  9  Fifth  layer  of  back. 
Posterior  intertransversalis.  10  Fifth  layer  of  back. 

The  atlas  has  a  small  spinous  process,  large  lateral  masses,  and  no  body. 
The  anterior  arch  forms  one-fifth  of  the  circumference,  the  posterior  arch  two- 
fifths  of  the  circumference,  and  the  lateral  masses  one-fifth  each.  The  attach- 
ment of  muscles  is  given  above.  There  is  a  groove  on  the  posterior  surface  of 
the  anterior  arch  for  the  articulation  of  the  odontoid  process  of  the  axis.  This 
process  is  held  in  place  by  the  transverse  ligament  which  passes  across  it  pos- 
teriorly, being  attached  to  the  inner  surface  of  the  lateral  masses.  Where  the 
posterior  arch  joins  the  lateral  masses  there  is  a  groove  (sinus  atlantis)  for  the 
vertebral  artery  and  suboccipital  nerve  (first  spinal  nerve),  the  nerve  lying  be- 
neath the  artery.  The  articulation  of  the  atlas  with  the  occiput  is  a  diarthrosis 
joint,  subclass  double  condylar  arthrosis,  having  all  the  movements  of  the  ball- 
and  socket  joint  (enarthrosis)  except  axial  rotation.     (Plate  XCV.) 

The  blood  supply  of  this  joint  is  the  vertebral  artery  and  sometimes  the 
ascending   pharyngeal   artery. 

The  nerve  supply  is  the  anterior  division  of  the  suboccipital  (first  cervical.) 

The  ligaments  are  the  anterior  occipito-atlantal, posterior  occipito-atlantal, 
two  capsular,  two  anterior  oblique  or  lateral  occipito-atlantal.      (Plate  CIX.) 

The  anterior  occipito-atlantal  ligament  is  attached  above  to  the  anterior 
margin  of  the  foramen  magnum,  below  to  the  upper  margin  of  the  anterior  arch 
of  the  atlas.  The  central  part,  which  is  a  continuation  of  the  anterior  common 
ligamenl  of  the  vertebral  column,  is  sometimes  called  the  superficial  part  of 
this  ligament.  The  lateral  portions,  which  are  continuous  with  the  capsular 
ligament,  form  the  deep  part.  In  front  of  this  ligament  are  the  Recti  capitis 
antici  minores  muscles.      H(  hind  is  the  central  odontoid  or  suspensory  ligament. 


ANATOMY    IN    A    NUTSHELL. 


261 


LESSON  LXXII. 

The  posterior  oceipito-atlantal  ligament  is  attached  above  to  the  posterior 
margin  of  the  foramen  magnum  from  condyle  to  condyle,  below  to  the  pos- 

PLATE  CVII. 


AN  ENTIRE  PACET  ABOVE 


A  DEMI-FACET  BELOW 


A  DEMI-FACET  ABOVE 


ONE  ENTIRE  FACET 


AN  ENTIRE  FACET. 
NO  FACET  ON  TRANSVERSE 


PROCESS.  WHICH  IS  RUDIMENTARY 


AN  ENTIRE  FACE1 
NO  FACET  ON  TRANSVERSE  PROCESS 


INFERIOR  ARTICULA  PROCESS 
CONVEX  AND  TURNED  OUTWARD 


The  Peculiar  Dorsal  Vert k hi;  b. 

terior  surface  and  upper  margin  of  the  posterior  arch  of  the  atlas.  This  liga- 
ment is  incomplete  on  each  side  for  the  passage  of  the  vertebra]  artery  into, 
and  the  suboccipital  nerve  from,  the  spinal  canal.     In  position  ii  corresponds 


262  ANATOMY    IN    A    NUTSHELL. 

to  the  ligamenta  subflava  which  are  below  the  axis  but  has  no  elastic  tissue  in 
its  composition.  In  front  this  ligament  is  attached  to  the  dura  mater  and  be- 
hind are  the  Rectus  capitis  posticus  minor  and  Superior  oblique  muscles. 

The  two  capsular  ligaments  are  attached  above  to  the  margins  of  the  con- 
dyL  -  of  the  occipital  bone  and  below  to  the  margins  of  the  articular  surfaces  of 
the  atlas.  Each  capsular  ligament  is  lined  with  synovial  membrane  which 
sometimes  communicates  with  the  synovial  membrane  of  the  transverse  odon- 
toid  ligament. 

The  two  anterior  oblique  or  lateral  occipito-atlantal  ligaments  are  situated 
in  front  of  the  external  part  of  the  capsular  ligament.  They  are  attached  above 
to  the  jugular  process  of  the  occipital  bone,  and  below  to  the  base  of  the  trans- 
verse process  of  the  atlas.     Their  direction  is  forward,  upward,  and  inward. 

The  articulation  of  the  lower  part  of  the  atlas  with  the  upper  part  of  the 
axis  is  a  diarthrodiaJ  joint,  subclass  arthrodial.  The  nerve  supply  is  the  loop 
between  the  first  and  second  cervical  nerves.  The  blood  supply  is  the  vertebral 
artery.  The  ligaments  are  anterior  atlanto-axial,  posterior  atlanto-axial, 
transverse,  and  two  capsular. 

The  anterior  atlanto-axial  ligament  is  attached  above  to  the  anterior  sur- 
face  and  lower  border  of  the  anterior  arch  of  the  atlas,  and  below  to  the  base 
of  the  odontoid  process  and  the  transverse  ridge  on  the  front  of  the  body  of  the 
axis.  It  is  continuous  on  each  side  with  the  capsular  ligaments.  In  front  in 
the  median  line  is  the  anterior  common  ligament  of  the  vertebral  column  which 
is  sometimes  called  the  superficial  anterior  atlanto-axial  ligament.  It  has  im- 
mediately in  front  the  Longus  colli,  then  the  Recti  capitis  antici  minores. 

The  posterior  atlanto-axial  ligament  takes  the  place  of  the  ligamenta  sub- 
flava of  the  joints  below  the  axis.  It  is  attached  above  to  the  posterior  surface 
and  lower  edge  of  the  posterior  arch  of  the  atlas  and  below  to  the  dorsal  aspect 
of  the  upper  edge  of  the  lamina  of  the  axis.  It  is  continuous  with  the  capsular 
Ligament  on  each  side.  It  is  perforated  on  each  side  by  the  second  cervical 
nerve.  In  front  it  is  connected  to  the  dura  mater,  behind  is  the  Inferior  ob- 
lique muscle. 

The  two  capsular  ligaments.  These  articulations  are  between  the  superior 
articular  surfaces  of  the  axis  and  inferior  articular  surface  of  the  atlas.  Each 
joint  has  a  loose  capsular  ligament  and  synovial  sac.  These  ligaments  are 
strengthened  in  front  and  behind  by  the  anterior  and  posterior  atlanto-axial 
ligaments. 

The  transverse  ligament  is  a  strong  fibrous  band  passing  from  the  tubercles 
on  the  inner  side  of  the  lateral  masses  of  the  atlas,  holding  the  odontoid  process 
in  place.  It  is  thicker  in  the  center  and  gives  fibers  which  pass  above  to  the 
basilar  process  of  the  occipital  and  some  passing  below  to  the  base  of  the  odon- 
toid process  and  body  of  the  axis,  thus  forming  a  crucial  ligament.  This  liga- 
ment divides  the  canal  of  the  atlas  into  two  parts,  a  small  anterior  one  which 
is  for  the  odontoid  process  and  a  large  posterior  one  for  the  spinal  cord, the  spinal 
acci  ssory  nerves,  the  spinal  arteries,  vertebral  arteries,  and  the  meninges  of  the 
cord. 

The  articulation  of  the  posterior  surface  of  the  anterior  arch  of  the  atlas 


PLATE  CVIII. 


TUBERCLE 


ARTICULAR  PART  OF  TUBERCLE 


SECOND  AND  THIRD  DICTATIONS 

OF  SERRATUS  MAGNUS  (0) 


STERNAL  END  FOR  COSTAL  CARTILAGE 


The  Second   and  Skykxth  Ribs. 
263 


264  ANATOMY    IN    A    NUTSHELL. 

with  the  odontoid  process  is  a  diarthrosis  joint,  subclass  trochoides.  Blood 
supply,  vertebral  and  ascending  pharyngeal  arteries.  Nerve  supply,  loop  be- 
tween the  first  and  second  cervical  nerves.  The  part  between  the  posterior 
surface  of  the  odontoid  process  and  the  transverse  ligament  is  a  syndesmo- 
odontoid  joint.  Each  of  these  joints  has  a  synovial  membrane.  The  synovial 
membrane  of  the  atlanto-odontoid  is  surrounded  by  a  capsular  ligament  of  the 
same  name  and  is  continued  with  the  occipito-atlantal  capsular  ligament.  It 
blends  with  the  anterior  occipito-atlantal,  atlanto-axial,  and  the  central  odon- 
toid ligaments.  The  synovial  sac  of  the  syndesmo-odontoid  joint  is  surrounded 
by  a  capsule.  This  sac  often  communicates  with  the  occipito-atlantal  synovial 
sac. 

The  ligaments  attached  to  the  odontoid  process  are  (1)  Occipito-axial  lig- 
ament (apparatus  ligamentosus  colli)  which  is  a  continuation  of  the  posterior 
common  Ligament  of  the  vertebral  column,  some  of  the  fibers  continuing  to  the 
anterior  margin  of  the  foramen  magnum  to  be  continued  by  the  dura  mater. 
This  cuvcrs  the  odontoid  process  and  its  ligaments. 

(2)  Crucial  ligament,  the  same  as  the  transverse  ligament. 

(3)  Two  lateral  odontoid  or  check  ligaments  passing  from  the  sides  of  the 
apex  of  the  odontoid  process  to  the  inner  surface  of  the  condyles  of  the  occipital 
bone,  their  direction  being  outward,  upward,  and  forward. 

(4)  The  central  odontoid  or  suspensory  ligament  is  attached  to  the  tip  of 
the  odontoid  process  below,  and  to  the  under  surface  of  the  anterior  margin  of 
the  foramen  magnum  above.  It  has  in  front  the  anterior  occipito-atlantal  lig- 
ament ami  behind  is  the  upper  division  of  the  crucial  ligament. 


LESSON  LXXIII. 

The  axis  is  the  second  cervical  vertebra.  (Plates  XCVI-XCVII.)  Its 
peculiarity  is  that  it  has  an  odontoid  process  which  is  in  reality  the  body  of  the 
atlas.  Its  spinous  process  is  bifid.  It  has  fourteen  pairs  of  muscles  attached. 
To  body  Longus  colli  1  Ant.  vertebral  region. 

Inferior  oblique  2   Fifth  layer  of  back. 

Rectus  capitis  posticus  major      3  Fifth  layer  of  back. 

Semispinals  colli  4  Fifth  layer  of  back. 

To  spinous  process    Spinalis  colli  5  Fourth  layer  of  back. 

[nterspinales  6  Fifth  layer  of  back. 

Multifidus  spinae  7  Fifth  layer  of  back. 

Supraspinales  8  Fifth  layer  of  back. 

Splenitis  colli  9  Third  layer  of  back. 

Anterior  intertransversalis         10  Fifth  layer  of  back. 
To  transverse  pro-    Posterior  intertransversalis         11   Fifth  layer  of  back. 
cess.  Levator  anguli  scapulae  12  Second  layer  of  back. 

Transversalis  colli  or  cervicis     13  Fourth  layer  of  back. 

Scalenus  medius  14  Lateral  vertebral  region. 

The  seventh  cervical  is  the  last  cervical  and  has  characteristics  of  both  cer- 
vical and  dorsal  vertebrae.     It  is  called  vertebra  prominens  on  account  of  its 


ANATOMY    IN    A   NUTSHELL. 


265 


large  spinous  process.  Its  transverse  process  may,  or  may  not,  have  the  costo- 
transverse foramina.  The  vertebral  artery  and  vein  more  often  pass  in  front 
of  the  transverse  process  than  through  its  foramen:  they  more  often  pass 
through  the  left  foramen  than  the  right  one  and  the  vein  more  often  than  the 
artery. 

The  anterior  tubercle  of  the  transverse  process,  which  is  an  analogue  of 
the  rib,  may  be  enlarged, making  a  rudely  developed  cervical  rib.  This  vertebra 
has  eighteen  pairs  of  muscles  attached  to  it. 

PLATE  CIX. 


POST.  0CC1PIT0-AXIAL      LIG. 


VERTICAL    LIG. 


ACCESSORY       ATLANTO-  AXIAL     LIG. 


Ligaments  of  Upper  Cervical  Ykktebr.e. 


To  bodv 


Longus  colli 

Trapezius 

Rhomboideus  minor 
Serratus  posticus  superior 

To  spinous  process   Splenius  capitis 
Mnltifidus  spina' 
[nterspinales 
S(  mispinalis  dorsi 

Spinalis  colli 

Anterior  inter!  ransversalis 
Posterior  Lntertransversalis 
Levatores  costarum 

To  transverse  Scalenus  posticus 

process  Scalenus  medius 


1  Ant.  vertebral  region. 

2  First  layer  of  back. 

.'!  Second  layer  of  hack. 

4  Third  layer  of  back, 

f)  Third  layer  of  back, 

(i  Fifth  layer  of  hack. 

7  Fifth  layer  of  hack. 

8  fifth  layer  of  hack. 

!>  Fourth  layer  of  back. 

10  Fifth  layer  of  back. 

1 1  Fifth  layer  of  hack. 

12  Thoracic  region. 

13  Lateral  vertebral  region 
11  Lateral  vertebral  region. 


266  ANATOMY   IN   A   NUTSHELL. 

To  transverse  Musculus  accessories  15  Fourth  layer  of  back. 

process.  Complexus  16  Fourth  layer  of  back. 

To  art  icular  Multifidus  spina?  17  Fifth  layer  of  back. 

process  Trachelo-mastoid  18  Fourth  layer  of  back. 


LESSON    LXIV. 

The  ligaments  of  the  vertebral  column  are:     (Plate  CIV.) 

1.  Ligaments  of  the  body: 

a.  Anterior  common. 

1).   Posterior  common. 

c.   Intervertebral  substance. 

el.  Lateral  or  short  ligament. 

2.  Ligaments  connecting  the  laminae: 

a.  Ligamenta  subflava. 

3.  Ligaments  connecting  the  articular  processes: 

a.  Capsular. 

4.  Ligaments  connecting  the  spinous  processes. 

a.  Supraspinous. 

b.  Interspinous. 

5.  Ligaments  connecting  the  transverse  processes : 

a.  Intertransverse. 

The  anterior  common  ligament  is  a  fibrous  band  extending  from  the  an- 
terior tubercle  of  the  atlas  to  the  base  of  the  sacrum.  Its  upper  part  makes  the 
anterior  atlanto-axial  ligament  and  its  lower  part  extends  to  make  the  anterior 
sacro-coccygeal  ligament.  It  is  broader  below  than  above  and  thickest  in  the 
dorsal  region  and  thinnest  in  the  cervical.  It  is  thicker  over  the  bodies  of  the 
vertebra?  than  over  the  intervertebral  substance.  The  interarticular  substance 
and  the  margins  of  the  bodies  of  the  vertebra?  give  attachment  to  the  ligament 
more  than  the  anterior  surface  of  the  bodies.  There  are  aperatures  at  the  sides 
of  the  median  position  of  the  body  for  the  passage  of  vessels.  This  ligament 
consists  of  three  layers  of  various  lengths  closely  intermingled;  the  superficial 
layer  passes  from  one  vertebra  to  the  fourth  or  fifth  above;  the  second  layer 
from  one  vertebra  to  the  second  or  third  above;  and  the  third  layer  connect 
adjacent  vertebra?. 

The  posterior  common  ligament  is  situated  along  the  anterior  part  of  the 
spinal  canal  upon  the  posterior  surface  of  the  bodies  of  the  vertebra?,  extending 
from  the  basilar  process  of  the  occipital  above,  to  the  coccyx  below,  its  upper 
pari  making  the  posterior  occipito-axial  ligament.  It  is  broader  above  (which 
is  the  reverse  of  the  .'interior  common  Ligament,)  thickest  in  the  dorsal  region, 
and,  like  t  he  anterior  one,  ii  is  attached  to  the  intervertebral  discs  and  adjacent 
margins  of  the  vertebrae.  It  is  narrow  and  thick  over  the  bodies  from  which  it 
is  separated  by  adipose  tissue  and  the  venae  basis  vertebrarum.  Opposite  the  in- 
tervertebral substance  it  gives  off  dentated  processes.  The  filum  terminale  of 
the  spinal  cord  blends  with  this  ligament  at  the  back  of  the  base  of  the  coccyx. 
Its  fibers  nre  not  so  bitenningled  as  those  of  the  anterior  common  ligament  and 


ANATOMY    IN    A    NUTSHELL. 


267 


consist  of  two  layers;  the  superficial  extends  from  one  vertebra  to  the  third  or 
fourth,  and  the  deeper  connect  adjacent  vertebrae. 

The  intervertebral  substance  or  discs  forms  about  one-fourth  of  the  spinal 
column.  They  conform  to  the  shape  of  the  bones  adjacent.  They  are  thicker 
at  the  anterior  than  at  the  posterior  border  in  the  cervical  and  lumbar  regions, 

PLATE  CX. 

BASILAR  PROCESS  OF  OCCIPITAL 


RECTUS     CAPITIS  _\ 
ANTICUS      MINOR 


RECTUS  CAPITIS  LATERALIS 


2ND  RIB 

SCALENUS    ANTICUS 

Muscles  of  Anterior  Vertebral  Region. 

thus  helping  to  form  the  curve  in  these  regions,  while  in  the  dorsal  or  thoracic 
region  they  are  of  a  uniform  thickness,  the  difference  in  the  thickness  of  the 
bodies  of  the  vertebra?  making  the  curve  in  this  region.  They  form  the  main 
bond  between  the  bodies  of  the  vertebra?;  they  are  compressible,  elastic,  and 
tough.  In  number  they  are  twenty-three,  extending  from  the  axis  to  the 
sacrum.  They  consist  of  an  outer  ring  and  an  inner  substance,  the  ring  is  com- 
posed of  fibro-cartilagenous  tissue  of  concentric  layers.  The  fibers  of  the  layers 
are  not  parallel  but  pass  into  the  layers  above  and  below.  The  central  sub- 
stance  has  cartilage  cells  set  in  fine  connective  tissue  matrix. 

The  lateral  or  short  vertebral  Ligaments  connect  the  adjacent  margins  of. 
the  bodies  of  the  vertebra?  between  the  anterior  and  posterior  common  liga- 
ments with  which  they  are  continuous.  In  the  dorsal  region  they  overlie  the 
stellate  ligaments  and  in  the  lumbar  they  radiate  towards  the  transverse  pro- 
cesses.    In  the  cervical  region  they  are  less  well  marked. 

The  Ligamenta  subflava  conned  the  lamina  between  the  axis  and  the  sac- 


268  ANATOMY    IN    A    NUTSHELL. 

rum.  They  arc  very  thin,  but  broad  and  long  in  the  cervical  region;  they  are 
thicker  in  the  dorsal,  being  very  thick  in  the  lumbar  region.  They  consist  of 
Yellow  elastic  tissue.  Their  fibers  are  almost  perpendicular.  They  are  at- 
tached  above  to  the  inner  surface  of  the  inferior  articular  process  and  the  inner 
surface  of  the  lower  margin  of  the  lamina  of  the  vertebrae;  below  to  the  inner 
surface  of  the  superior  articular  process  and  the  upper  margin  of  the  lamina. 
They  are  continuous  with  the  interspinous  ligament  at  the  root  of  the  spinous 
processes  and  help  to  form  the  capsular  ligament. 

The  capsular  ligaments  connect  the  articular  processes,  being  attached  along 
the  margins  of  the  articular  surfaces;  the  lateral  part  of  the  ligamenta  subflava 
forms  their  inner  portion.  Each  joint  is  lined  by  a  synovial  membrane.  These 
ligaments  are  short  and  tight  in  the  thoracic  region,  loose  in  the  cervical,  and 
intermediate  in  the  lumbar. 

The  supraspinous  ligaments  are  fibrous  bands  connecting  the  tips  of  the 
processes,  extending  from  the  tip  of  the  vertebra  prominens  to  the  first  sacral. 
It  is  continued  above  as  the  ligamentum  nuchae  and  below  along  the  spines  of 
the  sacrum. 

The  interspinous  ligaments  extend  in  all  regions  of  the  vertebral  column 
betweeB  the  spinous  processes  of  the  vertebrae,  running  from  root  to  apex. 
In  the  cervical  region  they  are  very  delicate  and  are  separated  by  the  Inter1 
spinales  muscles.     They  are  stronger  in  the  lumbar  than  in  the  dorsal  region. 

The  intertransverse  ligaments  extend  between  the  transverse  processes  of 
the  vertebrae;  in  the  cervical  region  they  are  often  absent, the  Intertransversales 
muscles  taking  their  place.  They  are  better  marked  in  the  dorsal  region;  in  the 
lumbar  region  thev  are  weak  and  membranous. 


LESSON  LXXV. 

Each  rib  has  the  following  points:     (Plate  CVIII.) 

Head  which  is  divided  by  a  ridge  into  two  facets,  and  these  articulate  with 
the  facets  on  the  bodies  of  the  dorsal  vertebrae ;the  ridge  giving  attachment  to 
the  interarticular  ligament. 

Neck,  about  an  inch  long, having  attached  to  its  upper  border  the  anterior 
costo-transverse  ligament,  to  its  posterior  surface  the  middle  costo-transverse 
ligament;  its  anterior  surface  is  smooth. 

Tuberosity,  at  the  junction  of  the  neck  with  the  shaft,  has  a  facet  for  artic- 
ulation with  the  transverse  process  of  the  next  lower  vertebra,  and  a  rough 
surface  for  the  posterior  costo-transverse  ligament. 

Shaft,  twisted  on  itself,  is  concave  internally,  convex  externally,  its  upper 
border  round  and  smooth,  its  lower  border  grooved  for  the  intercostal  vessels 
and  nerves.  A.1  its  external  extremity  is  an  oval  depression  for  the  insertion 
of  the  costal  cartilage. 

Angle,  just  in  front  of  the  tuberosity,  is  marked  by  a  rough  line,  to  which 
nre  attached  the  muscles  of  the  deep  layer  of  the  back. 

Bach  rib  is  developed  in  the  following  manner: 

Each  rib  has  thri  e  centers,  one  for  the  head,  one  for  the  shaft,  and  one  for 


PLATE  CXI. 


BIVENTER  CERVICIS 


RECTUS  CAPITIS  POSTICUS  MINOR 

OBLIQUES  CAPITIS  SUPERIOR 
RECTUS  CAPITUS  POSTICUS  MAJOR 
OBLIQUES  CAPITIS  INFERIOR 

TRACHELO     MASTOID 

SCALENI      MEDIUS    AND    POSTICUS 


VERTEBRAL    APONEUROSIS 


OBLIQUE     INTERNUS     ABDOMINIS 


ORIGIN     OF     ERECTOR  SPINAE 


Muscles  of  Back  (Deep  Layer). 
269 


270 


ANATOMY    IN    A    NUTSHELL. 


the  tuberosity.     The  last  two  ribs,  having  no  tuberosity,  are  developed  each 
by   two  centers. 

The  peculiar  ribs  are  the  first,  second,  tenth,  eleventh,  and  twelfth.  They 
respectively   present   the  following  peculiarities,  viz: 

First  Rib  is  broad,  short,  not  twisted,  has  no  angle,  only  one  facet  on 
the  head,  but  on  its  upper  surface  are  seen  two  grooves  for  the  subclavian 
artery  and  vein,  and  between  them  a  tubercle  for  the  Scalenus  anticus  muscle. 

Second  Rib  is  not  twisted,  its  tuberosity  and  angle  are  very  close  to- 
gether, and  its  upper  surface  presents  rough  surfaces  for  the  Serratus  magnus 
and  Scalenus  posticus  muscles. 

Tenth  Rib  has  but  one  facet  on  its  head. 

Eleventh  Rib  has  no  neck,  no  tuberosity,  and  but  one  facet  on  its  head. 

Twelfth  Rib  has  neither  neck,  angle,  tuberosity  nor  groove,  and  but 
one  facet. 

Muscles  of  the  Back. 

The  muscles  of  the  back  are  arranged  in  five  layers.  (Plates  XVIII-CXI) 
Those  in  the  fourth  layer  get  both  the  internal  and  external  divisions  of  the 
posterior  1  tranches  of  the  spinal  nerves.  The  external  divisions  supply  those 
in  the  third  layer.  The  internal  divisions  together  with  the  sub-occipital  and 
great  occipital  supply  those  in  the  fifth  layer.     (Plates  XVIII-CXI.) 


First  layer. 

1  Trapezius.     See  page  45. 

2  Latissimus  dorsi.     See  page  52. 

Second  layer. 

1  Levator  angulae  scapulae.     Page  54. 

2  Rhombodideus  minor.     Page  .1."). 
:'>  Rhomboideus  major.     Page  55. 

Third  layer. 

1  Serratus  posticus  superior. 

2  Serratus  posticus  inferior. 

3  Splenius  capitis. 
I  Splenius  colli. 

Fourth  layer. 

S  \cr.\l  AND  LUMBAR  REGIONS. 

1  Erector  spina'. 

DORSAL  REGION. 

2  Dio-costalis. 

.'5  Musculus  accessorius  ad  ilio-costalem 
I    Longissimus  dorsi. 
5  Spinalis  dorsi. 

I  i.i;\  [CAL  REGION. 

6  Cervicalis  ascendens. 

7  Transversalia  colli. 

8  Trachelo-mastoid. 
!»  Complexus. 


NERYKS. 

Spinal  accessory; 3rd  and  4th  cervical. 
Middle  or  long  subscapular. 

3rd  and  4th  cervical;  sometimes    5th. 
5th  cervical. 
5th  cervical. 

External  divisions  of  the  posterior 
branches  of  the  spinal  nerves,  in  their 
k  spective  regions. 


All  the  muscles  in  the  fourth  layer 
get  the  external  divisions  of  posterior 
branches  except  the  Spinalis  dorsi  and 
Spinalis  colli  and  the  Complexus. 


They  get  the  internal  divisions  of 
the  posterior  branches.  The  Com- 
plexus also  gets  the  sub-occipital  and 
the  great  oc(  ipital  nerves. 


ANATOMY    IX    A    NUTSHELL. 


271 


10  Biventer  cervicis. 

11  .Spinalis  colli. 

Fifth  layer. 

1  Semispinalis  dorsi. 

2  Semispinalis  colli. 

3  Multifidus  spinae. 

4  Rotatores  spina?. 

5  Supraspinales. 

6  Interspinales. 

7  Extensor  coccygis. 

8  Intertransversales. 

9  Rectus  capitis  posticus  major. 

10  Rectus  capitis  posticus  minor. 

11  Obliquus  capitis  superior. 

12  Obliquus  capitis  inferior. 


All  these  muscles  in  the  fifth  layer 
are  supplied  by  the  internal  divisions 
of  the  posterior  branches  of  the  spinal 
nerves  in  their  respective  regions,  ex- 
cept the  Recti  andObliqui,  and  they 
are  supplied  by  the  sub-occipital.  The 
Inferior  oblique  also  takes  the  great 
occipital  nerve. 


CUTANEOUS 


WITH     OCCIPITALIS    Ml 


SUPERIOR  OBLIQUE 
COMPLEXUS 


RECTUS  CAP. 
POSTERIOR    DIV 
ST.    CERVICAL 


PLATE  CXI  I. 

TO        SCALP 


AURICULAR 


INF.  OBLIQUE 
POSTERIOR     DIVISION  OF 
-ND.     CERVICAL 


POSTERIOR    DIVISION     OF 
RD      CERVICAL 


SPLENIUS       ssss^-ti 
COMPLEXUS.   =3^ 
TRACHELO-MASTdlO 


SKIN    OVER    TRAPEZIUS 

The  Posterior  Cervical  Plexus. 
Muscles  of  the  Third  L  wi:i;. 

Serratus  posticus  superior. — Description.  This  muscle  is  quadrilateral 
and  has  a  serrated  outer  margin.  The  inner  half  of  the  muscle  is  tendinous  and 
theouter  half  isfleshy.     It  takes  its  name  from  its  serrated  edgeand  its  position. 

Origin. — (1)   Ligamentum  nuchse,   (2)  spinous   processes  of  the  seventh 


272  ANATOMY    IN    A    NUTSHELL. 

cervical  and  first,  second,  third,  and  fourth  dorsal  vertebrae,  (3)  supraspinous 
ligament. 

Insertion. — Into  the  upper  borders  of  the  second,  third,  fourth,  and  fifth 
ribs  beyond  their  angles. 

Action. — To  assist  in  inspiration  by  raising  the  ribs  into  which  it  is  in- 
serted. 

\i:i;\  i:  Supply. —  External  divisions  of  the  posterior  branches  of  the  spinal 
nerves. 

Blood  Supply. — The  muscles  in  the  back  are  supplied  by  (1)  occipital, 
(2)  vertebral,  (3)  intercostal,  (4)  subclavian  (thyroid  axis),  (5)  lumbar  arter- 
ies.    This  applies  to  all  the  muscles  in  the  back. 

Serratus  posticus  inferior. — Description. — This  muscle  takes  its  name 
from  its  serrated  edge  and  its  position.  More  than  half  of  this  muscle  is  apon- 
eurosis, which  blends  with  the  posterior  layer  of  the  lumbar  fascia.  Its  outer 
portion  is  fleshy. 

Origin. — (1)  Spinous  processes  of  the  eleventh  and  twelfth  dorsal,  and 
first,  second,  and  third  lumbar  vertebrae,  (2)  supraspinous  ligament. 

Insertion. — Into  the  lower  borders  of  the  ninth,  tenth,  eleventh,  and 
twelfth  ribs  beyond  their  angles. 

Action. — It  assists  in  inspiration  by  depressing  the  lower  ribs,  and  making 
them  a  fixed  point  so  the  diaphragm  can  contract. 

Nerve  Supply. — External  divisions  of  the  posterior  branches  of  the  spinal 
nerves.  The  nerve  supply  of  the  remaining  muscles  of  the  back  is  given  in 
the  first  part  of  this  lesson. 

Splenius  capitis  and  Splenius  colli. — Description. — This  is  a  broad  muscle 
which  divides  above  into  two  portions  for  insertion.  It  takes  its  name  (band- 
age) on  account  of  it  holding  down  the  Complexus  and  other  muscles. 

Origin. — This  muscle  has  one  origin  and  two  insertions  and  may  be  called 
two  muscles.  (1)  Lower  one-half  of  the  ligamentum  nuchas,  (2)  spinous  pro- 
cesses of  the  seventh  cervical,  and  upper  six  dorsal  vertebrae,  (3)  supraspinous 
ligament. 

Insertion. — (Capitis  portion).  (1)  mastoid  process  of  temporal  bone, 
(2)  occipital  bone  beneath  the  superior  curved  line.  (Colli  portion)  into  the 
transverse  processes  of  the  first,  second,  and  third  cervical  vertebra?  (posterior 
tubercles.  I 

Action.—  It  flexes  the  head  and  neck,  laterally,  extends  them,  and  rotates 
the  face   to  same  side. 


LESSON  LXXVI. 

Muscles  of  the  Fourth  Layer  of  the  Back. 
Erector  Spinae. — Description. — This  muscle  and  its  continuations  fill  up 
the  vertebral  groove  on  each  side  of  the  spine.  In  the  sacral  region  this  muscle 
is  primed  and  tendinous.  In  the  lumbar  region  it  is  larger  and  fleshy.  In 
the  dorsal  region  it  divides  into  its  branches,  and  these  sub-divide.  This 
muscle  is  covered  in  the  lumbar  region bythe  lumbar  fascia;  in  the  dorsal  region 


ANATOMY    IN    A    NUTSHELL. 


273 


by  the  Serrati  muscles,  and  the  vertebral  fascia,  and  in  the  cervical  region  by  a 

laver  of  cervical  fascia.  +. . 

Origin. — (1)  Spines  of  the  eleventh  and  twelfth  dorsal  vertebrae,  (2)    all 

the  lumbar  and  sacral  spines,  (3)  supraspinous  ligament  of  all  these,  (4)   back 


RECTUS  LAKIIUS    ANTICUS    MAJOR 
RECTUS  CAPITIS   ANTICUS  MINOR 

RECTUS  CAPITIS  LATERALIS 


LONGUS      COLLI 

RECTUS     CAPITIS 

ANTICUS      MAJOR 


GENIO-HYOID 

THYRO-HYOID 

LONGUS    COLLI 
RECTUS     CAPITIS 
A'.TlCLiS      MAJOR 

DESCENnENS    CERVICIS 
COMMUNICANS    CERVICIS 

OMO-HYOID 
LONGUS    COLL 
RECTUS     CAPITIS 
ANTICUS     MAJOR 

SCALENUS      ANTICUS 
STERNO-HYOID 

STERNO     THYROIO 


PLATE  CXI  1 1. 

TWEIPTH  NERVE 

FIRST  CERVICAL  NERVE. 


TRAPEZIUS 


TRAPEZIUS 


SUPRA 

supra-sternal      clavicular 
The  Cervical  Plexus. 


SUPRA- ACROMIAL 


part  of  the  inner  lip  of  i lie  cresl  of  the  ilium .  (.">)  posterior  surface  of  the  sacrum 
external  to  the  spinous  processes. 

Insertion.-  This  muscle  extends  clear  to  the  head  by  it-  numerous  sub- 
divisions ami  these  are  its  insertion. 

Action. — To  extend  the  Lumbar  spine  on  the  pelvis. 

Iilo-costalis. — (Sacro-lumbalis.)  Description.  This  muscle  take-  its 
name  from  its  attachments  to  the  ilium  and  the  ril>s. 

Origin. — From  the  outer  part  of  the  Erector  spina'. 


274  ANATOMY    IN    A    NUTSHELL. 

Insertion. — Into  the  inferior  borders  of  the  angles  of  the  six  or  seven 
Lower  ribs.     It  sometimes  may  include  all  the  ribs. 

Action. — To  draw  down  the  chest  and  spine. 

Musculus  accessorius  ad  ilio-costalom  (ad  sacro-lumbalem.) — Description. 
—This  muscle  is  narrow  with  a  serrated  margin  on  each  side.  It  takes  its  name 
from  being  an  accessory  to  the  Ilio-costalis. 

Ork;ix. — From  the  upper  borders  of  the  angles  of  the  six  lower  ribs  by 
separate   tendons. 

Insertion. — (1)  Upper  borders  of  the  angles  of  the  six  upper  ribs,  (2) 
back  of  transverse  process  of  the  seventh  cervical  vertebra. 

Action. — To  assist  the  Erector  spina3. 

Longissimus  dorsi. — Description. — This  muscle  takes  its  name  from  its 
length  and  position. 

Origin. — (1)  From  the  middle  part  of  the  Erector  spina?,  (2)  transverse 
processes  of  the  lumbar  vertebra*,  (3)  middle  lamina  of  lumbar  fascia. 

Insertion. — (1)  Tips  of  transverse  processes  of  all  the  dorsal  vertebras, 
(2)  between  the  tubercles  and  angles  of  the  lower  ribs  (seventh  to  eleventh.) 

Action. — To  draw  down  the  chest  and  spine. 

Spinalis  dorsi. — Description. — This  muscle  takes  its  name  from  its  at- 
tachment to  the  spines  in  the  dorsal  region. 

Origin. — From  spinous  processes  of  eleventh  and  twelfth  dorsal  and  first 
and  second  lumbar  vertebra?. 

Insertion. — Into  the  spinous  processes  of  the  six  or  eight  upper  dorsal 
vertebra1. 

Action. — To  extend  the  dorsal  region  of  the  spine. 

Cervicalis  ascendens. — Description. — This  muscle  takes  its  name  from  its 
position  and  direction. 

Origin. — From  angles  of  the  four  or  five  upper  ribs. 

Insertion. — Posterior  tubercles  of  transverse  processes  of  fourth,  fifth 
and  sixth  cervical  vertebrae. 

Action. — Elevates  the  ribs,  if  the  cervical  vertebrae  are  the  fixed  point.  It 
extends  the  neck,  if  the  ribs  are  the  fixed  point.  If  only  one  acts  it  pulls  the 
neck    to    its   own    side. 

Transversalis  colli  (cervicis.) — Description. — This  muscle  takes  its  name 
from  its  attachment  to  the  transverse  processes,  and  its  insertion  in  the  neck. 

Origin. — From  upper  portion  of  transverse  processes  of  six  upper  dorsal 
vertebrae. 

Insertion.— Posterior  tubercles  of  transverse  processes  of  the  second  to 
the  sixth  cervical  vertebrae  (inclusive.) 

Action. — If  both  ad,  and  the  fixed  point  is  below,  they  extend  the  neck 
backward. 

Trachelo-mastoid. —  DESCRIPTION. — This  muscle  takes  its  name  from  its 
origin  and  its  insertion. 

Origin. — (1)  Transverse  processes  of  first  five  or  six  dorsal  vertebrae,  (2) 
articular  processes  of  the  three  or  four  lower  cervical  vertebra?. 

Insertion.-    Posterior  margin  of  mastoid  process  of  temporal  bone  be- 


ANATOMY    IX    A    NUTSHELL. 


275 


neath   the  insertion  of  the  Splenitis  capitis  and  the  Sterno-cleido-mastoid. 

Action. — If  both  act,  they  extend  the  head  backward.  If  only  one  acts  it 
turns  the  face  toward  the  shoulder  of  same  side. 

Complexus. — Description. — This  muscle  takes  its  name  from  the  com- 
plicated arrangement  of  its  muscular  bundles. 

Origix. — Tips  of  transverse  processes  of  from  two  to  seven  upper  dorsal 
vertebra?  and  seventh  cervical  vertebra1,  (2)  articular  processes  of  fourth,  fifth, 
and  sixth  cervical  vertebrae. 


PLATE  CXIV. 

PHRENIC    NERVE 


SUPaAST'PULAR    HERVE 


PNEUMOGASTRIC 

SUBCLAVIAN      ARTERY 

INNOMINATE     ARTERY 
EXTERNAL    JUGULAR  VEIN 


MEDIAN 


*WSOil  0-SP1RAL    N 


AXILLARY     ARTERY 


MUSCULOCUTANEOUS 


■SUBSCAPULAR     ARTERY. 


vpROFimni     ARTERY 

Thyroid  Axis  axd  Cords  of  Brachial  Plexus. 

Insertion. — Into  the  innermost  depression  between  the  two  curved  lines 
of  the  occipital  bone 

ACTION. — If  both  act  they  draw  the  head  backward,  if  only  one  ads  it 
draws  the  head  to  one  side,  and  with  the  face  turned  to  the  opposite  side. 

Biventer  cervicis. — Description. — This  muscle  is  one  of  the  so-called 
double  bellied  muscles,  and  is  situated  on  the  Inner  side  of  the  Complexus. 

Origin. — Transverse  processes  of  from  two  to  four  upper  dorsal  vertebrae. 

Insertion. — Superior  curved  line  of  the  occipital  bone. 

Action. — This  muscle  is  a  helper  to  the  Complexus. 

Spinalis   colli. — Description. — This    muscle    is   snail    and    connects    tic 


276  ANATOMY    IN    A    NUTSHELL. 

spinous  processes  in  the  cervical  region.  This  muscle  is  absent  in  about  twenty 
per  cent  of  the  cases. 

Origin. — (1)  Spinous  processes  of  the  fifth,  sixth,  and  seventh  cervical 
vertebrae,  (2)   and  occasionally  from  the  first  and  second  dorsal  vertebras. 

Insertion. — Spine  of  axis  and  third  and  fourth  cervical  vertebrae. 

Action. — To  approximate  the  spines  of  the  vertebrae. 


LESSON  LXXVII. 

Fifth  Layer  of  Muscles  of  Back. 

Semispinalis  dorsi. — Description. — This  muscle  takes  its  name  on  account 
of  its  inner  half  being  attached  to  the  spine,  and  its  situation  in  the  dorsal 
region. 

Origin. — From  transverse  processes  of  fifth,  sixth,  seventh,  eighth,  ninth, 
and  tenth  dorsal  vertebra?. 

Ixskrtion. — Into  the  spinous  processes  of  seventh  and  eighth  cervical, 
first,  second,  third,  and  fourth  dorsal  vertebrse. 

Action. — To  erect  the  spinal  column. 

Semispinalis  colli. — Description. — This  muscle  takes  its  name  from  the 
attachment  of  its  one-half  to  the  spines  in  the  cervical  region. 

Origin. — Transverse  processes  of  the  upper  five  or  six  dorsal  vertebra?. 

Insertion. — Into  the  spinous  processes  of  the  second,  third,  fourth,  and 
fifth  cervical  vertebrse. 

Action. — To  erect  the  spinal  column. 

Multindus  spinas — Description. — This  muscle  takes  its  name  from  its 
many  clefts. 

Origin. — (1)  Back  of  sacrum  as  far  as  the  fourth  sacral  foramen,  (2) 
aponeurosis  of  the  Erector  spina?  muscle,  (3)  Posterior  superior  spine  of  the 
ilium,  (4)  posterior  sacrc-iliac  ligament,  (5)  articular  processes  of  lumbar  ver- 
tebras (6)  transverse  processes  of  dorsal  vertebras,  (7)  articular  prosesses  of 
three  or  four  lower  cervical  vertebra?. 

Insertion. — Into  the  lamina?,  and  spinous  processes  of  all  the  vertebra? 
except  the  atlas. 

Action. — To  preserve  the  erect  position  of  the  spine  and  to  rotate  it. 

Rotatores  spinae. — Description. — This  muscle  takes  its  name  from  its 
functions.  There  are  generally  eleven  pairs,  but  they  may  be  found  in  the 
cervical  and  lumbar  regions. 

Origin.-  Upper  and  hack  parts  of  the  transverse  processes  in  the  dorsal 
region  i  I   t  he  S]  inc. 

Insertion.-  Lower  border  and  outer  surface  of  the  first  lamina  above  the 
oi  igin. 

Action. —  Assists  the  Mrlli.idus  spina?  to  rotate  the  spine,  turning  the  trunk 
to  i he  opposite  si  le. 

Suprasplnales.—  Description.-  These  muscles  lie  on  the  spinous  pro- 
c(  sses  in  t  he  cervical  r<  eion. 


PLATE  CXV. 


FRONTAL 


SUPRAORBITAL 
COMMUNICATING 
WITH  OPHTHALMIC 
ANGULAR 


LATERAL      NASAL- 


TRANSVERSE  FACIAL 


INFERIOR       u- 
CORONARY 


ANT,  TEMPORAL 
POST.  TEMPORAL 

DEEP   TEMPORAL 

INTERNAL  MAXILLARY 
OCCIPITAL 

TEMPORO-  MAXILLARY 


JUGULO  -CEPHALIC 


Lymphatics  and  Veins  of  Neck   \\i>  Kace. 
277 


278  ANATOMY    IN    A    NUTSHELL. 

Origin. — Spinous  process  and  external  to  the  process  immediately  above. 

Insertion. — Spinous  processes  immediately  above. 

Action. — Approximate  the  spinous  processes. 

Interspinales. — Description. — These  muscles  are  six  pairs  in  the  cervical 
region  (first  pair  between  axis  and  third  cervical.)  They  are  in  the  upper  and 
lower  dorsal,  but  absent  in  the  middle  dorsal.  There  are  four  pairs  between 
the  five  lumbar  vertebrae,  sometimes  one  above  and  one  below  these  pairs. 

Origin. — Spinous  process  below. 

Insertion. — Spinous  process  above. 

Action. — Approximate  the  spinous  processes. 

Intertransversales. — Description. — In  the  cervical  region  these  are  best 
developed,  and  are  in  pairs  (anterior  and  posterior)  passing  between  the  anter- 
ior and  posterior  tubercles  of  the  tranverse  processes.  Between  these  muscles 
pass  the  anterior  division  of  the  spinal  nerve.  There  are  seven  pairs  in  the  cer- 
vical region. 

In  the  dorsal  region  they  are  not  well  developed.  They  are  absent  in  the 
middle  dorsal.  In  the  lumbar  region  they  are  in  pairs — one  set  called  the 
intertransversales  laterales,  which  are  situated  between  the  transverse  pro- 
cesses. The  other  set  called  intertransversales  mediales  are  situated  between 
the  accessory  process  of  one  vertebra  and  the  mammillary    process  of  the  next. 

Origin. — In  a  transverse  process  below. 

Insertion. — Transverse  process  immediately  above. 

Action. — Approximate  the  transverse  processes. 

Extensor  coccygis. — Description. — This  muscle  extends  over  the  lower 
part  of  the  posterior  surface  of  sacrum  and  coccyx. 

Origin. — Last  sacral  or  first  coccygeal  vertebra. 

Insertion. — Lower  part   of  the  coccyx. 

Action. — To  extend  the  coccyx. 

Rectus  capitis  posticus  major. — Description. — This  muscle  becomes  broad 
as  it  ascends. 

Origin. — Spinous  process  of  axis. 

Insertion. — Inferior  curved  line  of  the  occipital  bone  and  surface  of  bone 
below. 

Action. — To  rotate  the  cranium  with  atlas,  around  the  odontoid  process 
of  the  axis. 

Rectus  capitis  posticus  minor. — Description. — This  muscle  is  the  smallest 
of  the  muscles  in  this  region. 

Origin. — Tubercle  on  posterior  arch  of  atlas. 

Insertion. — Occipital  bone  beneath  the  inferior  curved  line. 

Action. — To  draw  the  head  backward. 

Obliquus  capitis  superior. — Description. — This  muscle  is  narrow  below 
but  wide  above. 

Origin. — Upper  surface  of  transverse  process  of  atlas. 

Insertion. — Occipital  bone  between  the  superior  and  inferior  curved  lines 
external   to   the  Complexus. 

ACTION. — To  draw  the  head  backward  and  rotate  cranium. 


PLATE  CXVI. 


ORBICULARIS    PALPEBRASUM 

ANGULAR 
LATERALIS       NASI 


ORBICULARIS        .N^- 
ORIS #§Hs 


Mmm 


Ir^T 


HYPO-GLOSSAL  N 

STERNO  HYOID- 
CRICOID     THYROID     A. 

STERNO  THYROID- 


WWi'M  -'7  i.'-V    'A 


V  '  *~ <  Or  "l\\\  \C 


ASCENDING       PHARYNGEAL 


LOOP  OF  COMMUNICATION  BETWEEN      HYPO- 
GLOSSAL N.   AND    CERVICAL    PLEXU! 


The  External  Carotid  Artery. 
279 


280  ANATOMY    IX    A    NUTSHELL. 

Obliquus  capitis  inferior. — Description. — This  muscle  is  larger  than  the 
superior  one. 

Origin.— Apex  of  axis. 

Insertion.  -  Lower  and  back  part  of  transverse  process  of  atlas. 

A.<  riON. — To  rotate  the  arias  with  cranium. 

The  -kin  of  the  back  is  supplied  by  posterior  divisions  of  spinal  nerves. 
The  internal  branch  of  the  posterior  divisions  of  the  upper  six  dorsal  uerves  are 
cutaneous,  while  the  external  branches  of  the  posterior  divisions  of  the  lower 
six  dorsal  nerves  are  cutaneous.  The  external  divisions  of  the  upper  and 
the  internal  divisions  of  the  lower  six  have  no  cutaneous  distribution. 

The  sacro-vertebral  articulation  is  supplied  by  the  fourth  and  fifth  lumbar  and 
sympathetic  nerves.  The  costo-central  articulations  are  supplied  by  the  an- 
terior divisions  of  the  spinal  nerves.  The  costotransverse  articulations  are  sup- 
plied by  the  posterior  division-  of  the  spinal  nerves.  The  sacro-iliac  articu- 
lations are  supplied  by  the  posterior  divisions  of  the  first  and  second  sacral 
nerves,  the  superior  gluteal  nerve,  and  sacral  plexus.  The  saero-eoccygeal 
articulation  is  supplied  by  the  fourth  and  fifth  sacral  and  coccygeal  nerves. 
The  ribs  and  vertebra'  an-  supplied  by  the  gray  rami  communicantes. 


LESSON  LXXVIII. 
Triaxoles  of  the  Neck.     (Plate  XIV.) 

The  side  of  the  neck  is  in  the  form  of  a  rectangle,  bounded,  above  by  the 
lower  margin  of  the  jaw-bone  and  a  line  continued  from  the  angle  of  the  jaw  to 
the  mastoid  process;  below,  by  the  clavicle;  posteriorly,  by  the  Trapezius;  and 
anteriorly  by  the  median  line  of  the  neck.  This  rectangle  is  divided  into  two 
triangles  by  the  Sterno-cleido-mastoid.  The  anterior  one  is  bounded  in  front 
by  an  imaginary  line  behind  by  the  Sterno-cleido-mastoid.  and  above  by  the 
lower  jaw-bone.  The  posterior  one  i-  bounded  in  front  by  the  Sterno-cleido- 
mastoid,  behind  by  the  Trapezius,  and  below  by  the  clavicle.  The  Omo-hyoid 
divide-  these  triangles  into  two  others  and  the  Digastric  divides  the  upper  one 
of  the  anterior  triangles  into  two  other  triangles.  The  Digastric  pierces  the 
Stylo-hyoid  which  help-  to  make  the  boundary  line  of  the  sub-maxillary  tri- 
angle. Then  these  muscles  divide  the  rectangle  on  the  side  of  the  neck  into  five 
triangles,     (li  Tin.  [nferiok  carotid  triangle,  or  triangle  of  necessity, 

of  Ml  -(  !  I.\i;  TRIANGLE.  (2)  TtlE  SUPERIOR  CAROTID  TRIANGLE,  or  TRIANGLE 
01  ELECTION.  (3)  Till.  SUBMAXILLARY,  Or  DIGASTRIC  TRIANGLE.  (4)  THE 
OCCIPITAL    TRIANGLE.       (5)    Till.    SUBCLAVIAN,  Or    SUPRACLAVICULAR    TRIANGLE. 

All  these  five  triangles  have  a  roof,  boundary  lines,  and  contents.  The  roof  of 
them  b  made  by  skin,  superficial  fascia.  Platysma  myoides,  and  deep  fascia. 
The  Inferior  carotid  triangle  in  addition  to  this  has  the  superficial  cervical  nerve 
ramifying  in  it-  roof.  Righl  beneath  this  roof  are  the  Sterno-hyoid  and  Sterno- 
thyroid. By  -one  these  two  muscles  are  called  the  floor,  hut  the  Longus  colli 
and  Scalenus  amicus  and  pari  of  the  Rectus  capitis  anticus  major  form  the  floor. 
This  triangle  is  bounded  in  fhont  by  the  median  line. above  by  the  anterior 


PLATE  CXVII. 


FRONTAL  SINUS 


PRINCIPES  CERVK.S 
A  BRANCH  OF   OCC.PITAL 


ASCENDING  PHARYNGEAL 


PROFUNDA  CERVi:iS 
STERNO-MAS'OiD 


CRICOID      CARTILAGE 


TRACHEA 


FIRST  RIB 

SUP.  INTERCOSTAL 
1ST        AORTIC     INTERCObML 
SECOND  RIB. 


Til  E    [NTERNAL    (  '  VROTID    A.RTERY. 

2. SI 


282  ANATOMY    IN    A    NUTSHELL. 

belly  nf  the  Omohyoid,  and  below  by  the  inferior  part  of  the  Sterno-cleido- 
mastoid.  .lust  beneath  the  anterior  border  of  the  Sterno-cleido-mastoid  is  the 
common  carotid  sheath  which  is  described  in  connection  with  this  triangle, 
although  it  is  under  this  muscle.  This  sheath  contains  the  common  carotid 
artery  internally,  the  internal  jugular  vein  externally,  and  the  pneumogastric 
nerve  between  the  two  but  on  a  plane  posterior  to  them.  This  sheath  is  bound- 
ed i\  front  by  branches  from  the  loop  of  communication;  on  the  inner  side 
by  the  trachea,  thyroid  gland,  and  the  lower  part  of  the  larynx;  behind  by 
the  inferior  thyroid  artery,  re<  urrent  laryngeal  nerve  and  the  sympathetic  nerve. 

The  second  triangle,  superior  carotid,  or  triangle  of  election,  is  bounded 
below  by  the  anterior  belly  of  the  Omo-hyoid;  behind  by  the  Sterno-cleido - 
mastoid; above  by  the  Digastric.  Its  roof  is  made  of  skin,  superficial  fascia, 
Platysma  myoides,  and  deep  fascia.  Its  floor  is  made  of  four  muscles,  Thyro- 
hyoid. Hyo-glossus,  Inferior  constrictor,  and  Middle  constrictor.  The  external 
carotid  artery  has  eight  branches,  five  of  which  are  in  this  triangle,  viz.,  superior 
thyroid,  lingual,  facial,  ascending  pharyngeal,  and  occipital,  with  their  corres- 
ponding veins,  all  of  which  empty  into  the  internal  jugular,  except  the  occipital 
which  may  empty  into  the  external  jugular. 

The  third  triangle,  or  digastric,  or  submaxillary  niangle,  is  bounded  in  fkont 
by  the  anterior  belly  of  the  Digastric; behind  by  the  Stylo-hyoid  perforated  by 
the  posterior  belly  of  the  Digastric; and  above  by  the  mandible  and  a  line  drawn 
from  the  angle  of  the  jaw  to  the  mastoid  process.  Its  roof  is  made  of  the  skin, 
superficial  fascia,  Platysma  myoides,  deep  fascia,  with  the  seventh  nerve  ram- 
ifying in  it.  Its  Moor  is  formed  by  the  Mylo-hyoid  ami  Hyo-glossus.  This 
triangle  is  divided  into  two  other  triangles  by  the  Stylo-maxillary  ligament, 
the  anterior  one  of  which  contains  the  submaxillary  gland  and  the  posterior 
one   contains   the   parotid  gland. 

The  occipital  triangle  is  bounded  in  front  by  the  Sterno-cleido-mastoid, 
below  by  the  posterior  belly  of  the  Omo-hyoid, and  behind  by  the  Trapezius. 
Its  roof  is  made  of  the  skin,  superficial  fascia,  Platysma  myoides,  and  deep 
fascia.  Its  floor  from  above  downward  and  inward  is  formed  by  the  Splenius 
capitis,  Levator  anguli  scapulae,  Scalenus  posticus  and  Scalenus  medius.  The 
spinal  accessory  nerve  crosses  this  triangle  from  the  Sterno-cleido-mastoid  to 
the  Trapezius.  A  row  of  lymphatic  nodes  lie  along  the  posterior  border  of  the 
Sterno-cleido-mastoid    in    this    triangle. 

The  subclavian  or  supraclavicular  triangle  is  bounded  above  by  the  pos- 
terior belly  of  the  <  )mo-h void. in  front  by  the  Sterno-cleido-mastoid, and  below 
by  the  clavicle.  Its  roof  is  made  by  the  skin,  superficial  fascia,  Platysma 
myoides,  and  deep  fascia  and  has  the  suprascapular  vessels  and  nerve  lying  in 
it.  Its  floor  is  made  of  the  digitations  of  the  Serratus  magnus,  Scalenus  pos- 
ticus. Scalenus  medius,  and  part  of  the  first  rib.  It  has  a  few  lymphatic  glands 
in  it. 

Tiir.  Suboccipital  Triangle.     (Plate  CXI.) 

The  suboccipital  triangle  is  bounded  EXTENALLY  by  the  Superior  oblique; 
below  by  the  Inferior  oblique,and  internally  by  the  Rectus  capitis  posticus 
major.     The  floor  of  this  triangle  is  formed  by  the  posterior    occipito-atlantal 


PLATE  CXVIII. 


RIGHT  POSTERIOR  CEREBRAL 
LEFT  POSTERIOR  CEREBRAL 


POSTERIOR  COMMUNICATING 

MIDDLE  CEREBRAL 

RIGHT  ANTERIOR  CEREBRAL 

OPHTHALMIC  ARTERY 


OCCIPITAL  ARTERY 
PRINCEPS  CERVICIS 

SUPERFICIAL  BRANCH  OF  PRINCEPS  CERVICIS 

ASCENDING  CERVICAL 


TRANSVERSE  CERVICAL 
POSTERIOR  SCAPULAR 

ACROMIAL  BRANCH 
SUBSCAPULAR  BRANCH 
SUPRASPINOUS   BRANCH 

ANTERIOR   CIRCUMFLEX 

INFRASPINOUS  BRANCH  '" 
POSTERIOR  CIRCUMFLEX 

LONG  THORACIC 

SUBSCAPULAR 

DORSAL  SCAPULAR 

INFRA  SCAPULAR  BRANCH 

SUBSCAPULAR 


SECOND  AORTIC 
NTERCOSTAL 
THIRD  AORTIC 

INTERCOSTAL. 


The  Arteries  From  Arch  of  Aokta  to  Circle  of  Willis. 

283 


284  ANATOMY    IN    A    NUTSHELL. 

ligament  and  the  posterior  arch  of  the  atlas,  and  its  roof  is  made  by  the  Com- 
plexus  muscle.  The  vertebral  artery  lies  in  a  groove  on  the  upper  surface  of 
the  posterior  arch  of  the  atlas  in  this  triangle.  The  suboccipital  nerve  enters 
this  triangle  between  the  vertebral  artery  and  the  arch  of  the  atlas.  The  deep 
cervical  vein  begins  in  this  triangle. 


LESSON  LXXIX. 
Arteries. 

The  pulmonary  artery  (Plate  ( 'XXVIII)  arises  from  the  left  side  of  the 
base  of  the  right  ventricle  in  front  of  the  aorta.  It  passes  upward  and  back- 
ward,beingtotheleftsideandin  front  of  the  ascending  aorta.  It  is  about  two 
inches  long  and  ends  under  the  transverse  aorta  where  it  divides  into  the  right 
pulmonary  artery  and  the  left  pulmonary  artery.  This  artery  and  the  ascend- 
ing aorta  are  enclosed  in  a  common  prolongation  of  the  serous  pericardium. 
The  right  pulmonary  artery,  which  is  larger  and  longer  than  the  left,  passes 
behind  the  ascending  aorta  and  the  superior  vena  cava  where  it  pierces  the 
pericardium.  It  divides  into  the  branches  at  the  root  of  the  lung,  one  branch 
being  for  the  upper  lobe  of  the  light  lung  and  the  other  for  the  lower  lobe. 
The  branch    which  passes  to  the  middle  lobe  is  derived  from  the  upper  branch. 

The  left  pulmonary  artery  passes  in  front  of  the  descending  aorta  and  the 
left  bronchus  to  end  in  the  root  of  the  left  lung  where  it  divides  into  an  upper 
branch  for  the  upper  lobe  and  a  lower  branch  for  the  lower  lobe. 

The  remains  of  the  ductus  arteriosus  passes  from  the  left  pulmonary  artery 
to  the  inferior  surface  of  the  transverse  aorta. 

The  aorta  begins  at  the  upper  part  e>f  the  left  ventricle  and  passes  upward 
to  the  right,  it  then  arches  to  the  left  and  backward.  It  now  elescends  on  the 
lefl  side  of  the  vertebral  column  to  pass  through  the  aortic  opening  of  the 
Diaphragm  and  it  ends  opposite  the'  fourth  lumbar  vertebra  where  it  elivides 
into  a  right  and  left  common  iliac  artery.  The  aorta  has  the  following  divi- 
sions; 1  '  Ascending,  (2)  Transverse,  (3)  Descending,  and  this  elescending  por- 
tion is  divided  into  thoracic  and  abdominal.  The  part  above  the  Diaphragm 
is  the  thoracic  aorta  and  the  pari  below  the  Diaphragm  is  the  abdominal  aorta. 
The  ascending  portion  commences  behind  the  left  half  of  the  sternum  at  the 
level  of  the  lower  border  of  the  third  costal  cartilage.  It  passes  obliquely  up- 
ward and  forward  to  the  righl  where  it  ends  at  the  upper  boreler  of  the  second 
righl  chondro-sternal  articulation.     It  is  about  two  inches  in  length. 

The  Relations  of  the  Ascending  Aorta  are: 

I.\  Front.— (1)  Pulmonary  artery,  (2)  Right  auricular  appendix.  (3) 
Pericardium,  i  1     Righl  pleura  and  lung,  (5)  Remains  of  thymus  gland. 

Behind. — (1)  Righl  pulmonary  artery.  (2)    Left  auricle. 

Righi  Side.     (1)  Superior  vena  cava,  (2)   Right  auricle. 

Left  Side.-    Pulmonary  artery. 

The  Transverse  aorta  (arch)  (Plate  CXXVIII)  is  a  continuation  of  the 
ascending  aorta  from  the  upper  bonier  of  the  second  right  e'hondro-sternal 
articulation.     It  arches  to  the  left   and  backward  with  its  e-onvexity  upward 


ANATOMY    IN    A    NUTSHELL. 


2v") 


and  ends  at  the  left  side  of  the  lower  border  of  the  fourth  dorsal  vertebra  from 
which  place  it  is  called  thoracic  aorta.  The  upper  border  of  the  arch  is  about 
an  inch  below  the  upper  margin  of  the  sternum. 

Relations  of  the  Arch  of  the  Aorta. 

Above. — (1)  Left  innominate  vein.  (2)  Innominate  artery.  (3)  Left  caro- 
tid artery.  (4)   Left  subclavian  artery. 

PLATE  CXIX. 


ANTERIOR  JUGULAR  VEIN 


COMMON  CAROTID  ARTERY 
INTERNAL    JUGULAR    VE 


OUTER     CERVICAL  FASCIA. 

MIDDLE  CERVICAL  FASCIA. 
.COMMON  CAROTID  ARTERY 

UGULAR    VEIN 
PNEUMOGASTRIC 
NERVE 


The  Cervical  Fascia. 

Below.— (1)  Eifurcaticn  cf  pulircnary  artery.  (2)  Remains  cf  .hums 
arteriosus,  (3)  Superficial  cardiac  plexus,  (4)  Lef1  recurrent  laryngeal  nerve, 
and   (5)    L<  f1  bronchus. 

[n  Front.— (1)   Pleurae  and  lungs,  (2)   Remains  of  thymus  gland,  (3)  Left, 


286  ANATOMY    IN    A    NUTSHELL. 

pneumogastric  nerve,  (4)  Left  phrenic  nerve,  (5)  Superficial  cardiac  nerves 
(6)  Left  superior  intercostal  vein. 

Behind. — (1)  Trachea,  (2)  Deep  cardiac  plexus,  (3)  Oesophagus,  (4) 
Thoracic  duct.  (5)  Left  recurrent  laryngeal  nerve. 

The  Relations  of  the  Thoracic  Aorta  are:  (Plate  CXXVIII.) 

I\  Front. — (1)  Root  of  left  lung,  (2)  Pericardium,  (3)  Oesophagus,  (4) 
]  Haphragm. 

Behind. — (1)  Vertebral  column,  (2)  Superior  and  inferior  azygos  minor 
veins. 

Right  Side. — (1)  Oesophagus  (above),  (2)  Vena  azygos  major,  (3)  Thorac- 
ic  dud. 

Left  Side. — (1)  Pleura,  (2)  Left  lung,  (3)  Oesophagus  (below.) 

The  ascending  aorta  has  the  right  coronary  and  the  left  coronary  artery 
which  have  been  described  with  the  heart.  The  branches  of  the  arch  of  the 
aorta  arc  (1)  innominate,  (2)  left  common  carotid,  (3)  left  subclavian.  The 
branches  of  the  thoracic  aorta  are  (1)  pericardiac,  (2)  bronchial,  (3)  oesopha- 
geal. (4)   posterior  mediastinal,  (o)  intercostal. 


LESSON  LXXX. 

The  innominate  artery  often  called  brachio-cephalic  has  its  beginning 
opposite  the  fourth  dorsal  vertebra  just  in  front  of  the  left  common  carotid. 
It  is  the  largest  of  the  branches  of  the  arch  of  the  aorta.  At  the  upper  border 
of  the  right  sterno-clavicular  articulation  it  divides  into  the  right  common 
carotid  and  the  right  subclavian.  It  is  from  an  inch  and  a  half  to  two  inches 
long  and  has  no  branches  as  a  rule,  but  the  thyroidea  ima  may  arise  from  it. 

The  Relations  of  the  innominate  artery  are  as  follows; 

1\  Front. — (1)  Sternum.  (2)  Sterno-hyoid  and  (3)  Sterno-thyroid  muscles, 
(4)  Remains  of  the  thymus  gland.  (5)  Left  innominate  vein,  (6)  Right  inferior 
thyroid  vein,  (7)  Inferior  cervical  cardiac  branch  from  right  pneumogastric 
nerve. 

Behind. — Trachea. 

Right  Side. — (1)   Right  innominate  vein,  (2)   Right  pneumogastric  nerve. 

Pleura. 

Left  Side. — (1)  Remains  of  thymus  gland.  (2)  Left  carotid  artery,  (3) 
Lef1   inferior  thyroid  vein,  (4)  Trachea. 

The  rijrht  common  carotid  artery  (Plates  CXVI-CXVII)  arises  from  the 
innominate  at  the  upper  border  of  the  right  sterno-clavicular  articulation.  It 
passes  obliquely  upward  and  divides  into  the  external  carotid  and  internal 
carotid  at  the  upper  border  of  the  thyroid  cartilage  opposite  the  fourth  cervical 
vertebra. 

The  left  common  carotid  artery  comes  from  the  highest  part  of  the  arch  of 
the  aorta  and  passes  upward  behind  the  left  slerno-calvicular  articulation  to 
divide  into  the  external  carotid  and  internal  carotid  at  the  upper  border  of  the 
thyroid  cartilage  opposite  the  fourth  cervical  vertebra.  These  arteries  are 
enclosed  in  a  common  sheath  of  cervical  fascia  with  the  internal  jugular  vein 


ANATOMY    IX    A    NUTSHELL. 


287 


and  pneumogastric  nerve.  The  internal  jugular  vein  lies  external  to  the  artery 
while  the  pneumogastric  nerve  is  between  the  internal  jugular  vein  and  com- 
mon carotid  artery  but  on  a  plane  posterior  to  them.  Occasionally  a  thyroid 
branch  passes  from  this  artery. 

The  Relations  of  the  Left  Common  Carotid  Artery  in  the  thorax  is  as  fol- 
lows: 

Ix  Front. — (1)  Sternum,  (2)  Sterno-hyoid  and  (3)  Sterno-thyroid  muscles. 

PLATE    CXX. 


SUPERIOR  CORNU    OF 


THYROID     CARTILAGE 


CRICOID  CARTILAGE 


The  Trachea. 


(4)   Left  innominate  vein,  (5)  Remains  of  thymus  gland. 

Behind.— (1)  Trachea.  (2)  Oesophagus,  (3)  Thoracic  duct.  (4)  Left  sub- 
clavian   artery. 

Internally. — (1)  Innominate  artery,  (2)  Inferior  thyroid  veins.  (3) 
(3)  Remains  of  thymus  gland. 

Externally. — (1)  Left  pneumogastric  nerve,  (2)  Left  pleura,  (.'!)  Left 
lung.  (4)   Left  subclavian  artery. 


288  ANATOMY    IN    A    NUTSHELL 


LESSON  LXXXI 

The  Relations  of  the  Right  Common  Carotid  and  the  Left  Common  Carotid 
arteries  tin  the  neck). 

I\  Front. — (1)  Integument,  (2)  Superficial  fascia,  (3)  Deep  cervical 
fascia,  (4)  Platysma myoides,  (5)  Sterno-mastoid,  (6)  Sternohyoid.  (7)  Sterno- 
thyroid. (8)  Omo  -hyoid,  (9)  Descendens  and  Communicans  nerves.  (10 
Sterno-mastoid  artery.  (11)  Superior  thyroid  vein,  (12)  Middle  thyroid  vein.. 
13)   Anterior  jugular   vein. 

Behind. — (1)  Longus  colli,  (2)  Rectus  capitis  amicus  major,  (3)  Sym- 
pathetic nerve,  (4)   Inferior  thyroid  artery.  (.">)   Recurrent  laryngeal  nerve. 

Externally.— (1)    Internal   jugular   vein.    (2)    Pneumogastric   nerve. 

Internally. — (1)  Trachea,  (2)  Thyroid  gland,  (3)  Recurrent  laryngeal 
nerve.  (4)    Inferior  thyroid  artery.  (5)   Larynx.  (6)   Pharynx. 

The  common  carotid  arteries  at  the  root  of  the  neck  are  close  together  and 
■  iii  ply  situated,  but  higher  in  the  neck  they  become  separated  and  are  more 
superficial.  The  common  carotid  artery,  internal  jugular  vein  and  the  pneu- 
mogastric nerve  all  lie  in  a  common  sheath. 

The  external  carotid  artery  is  a  branch  from  the  common  carotid  artery  at 
the  upper  border  of  the  thyroid  cartilage,  from  which  place  it  runs  upward 
and  forward,  then  backward  between  the  external  auditory  meatus  and  the 
neck  of  the  c<  ndyle  of  the  mandible  (lower  jaw).  It  now  divides  into  a  super- 
ficial temporal  and  internal  maxillary  arteries.  It  lies  in  the  superior  caroitd 
triangle  (triangle  of  (lection)  and  passes  through  the  substance  of  the  parotid 
gland.  It  is  superficial  to  and  nearer  to  the  median  line  of  the  neck  than  the 
internal  carotid  artery  at  its  beginning.  The  branches  <  f  the  external  carotid 
artey  are,  (1)  superior  thyroid.  (2)  lingual.  (3)  facial,  which  are  anterior 
branches;  (4)  occipital  ,(5)  posterior  auricular,  which  are  posterior  branches; 
-rending  pharyngeal,  which  is  an  ascending  branch;  (7)  superficial  tem- 
poral,  (8)   interna]   maxillary,  which  are'  terminal  branches. 


LESSON  LXXXI  I. 

The  superior  thyroid  branch  (Plate  CXVI.)  arises  just  below  the  great 
cornu  of  the  hyoid  bone,  and  passes  inward  and  upward  across  the  superior 
carotid  triangle  from  which  place  it  passes  downward  and  forward  to  the  upper 
part  of  the  thyroid  gland,  after  passing  under  the  Sterno-hyoid,  Sterno-thyroid 
and  Omo-hyoid  muscles.  Besides  giving  branches  to  these  muscle's  and  the 
thyroid  gland,  it  gives  off  (1)  a  hyoid  branch  which  passes  along  the'  lower 
border  of  the'  hyoid  bone'.  (2)  Sterno-mastoid  branch,  also  called  super- 
ficial des<  ending,  which  passes  to  the  Sterno-mastoid  muscle  after  running 
downward  and  outward  across  the  sheath  of  the'  common  carotid  artery.  (3) 
Superior  laryngeal,  which  passes  with  the  superior  laryngeal  nerve  to  the 


PLATE  CXXI. 


BAND  CONNECTING  THYMUS  WITH 
HTOID  BONE 


The  Heart,  Thyroid  Gland  (and  Lungs  Turned  Outward). 

289 


290 


ANATOMY    IX    A    NUTSHELL. 


larynx    under   the   Thyro-hyoid   muscle.     (4)  Cricothyroid    branch    which 
runs  across  the  cricothyroid  membrane. 

The  lingual  artery  (Plate  CXVI.)  first  passes  obliquely  upward  and  in- 
ward across  the  Middle  constrictor  muscle  to  the  greater  cornu  of  the  hyoid 
bone.     It  now  passes  horizontally  forward  on  the  Middle  constrictor  muscle 

PLATE  CXXII. 


GRFATER    CORNU  OF  HYOID    BONE- K'F>GHIT!-S     // 


LESSER    CORNU  OF   HYOID    BONE 

MEDIAN      PORTION      OF 
THYRO-HYOID      MEMBRANE 

POMUN ADAM 


GROOVE  FOR  SUBCLAVIAN  ARTERY 


INTERNAL  LARYNGEAL  NERVE 

SUPERIOR  LARYNGEAL  ARTERY 
SUPERIOR  THYROID  ARTERY 
THYROID  CARTILAGE 

CRICO-THYROID  MEMBRANE 
LEVATOR  GLANDULAE   THYROIDEA  MUSCLE 


GROOVE  FOR  SUBCLAVIAN  ARTERY 


Anterior  View  of  Lungs. 

under  the  tendon  of  the  Digastric  muscle.  Stylo-hyoid  and  the  Hyo-glossus 

muscle.  The  Hyo-glossus  muscle  separates  the  lingual  artery  and  the  twelfth 
cranial  nerve  (hypoglossal).  The  artery  now  passes  vertically  upward  between 
the  Hyo-glossus  and  Genio-hyo-glossus  to  the  under  surface  of  the  tongue  where 
it  takes  the  name  of  ranine  artery.  In  this  position  it  accompanies  the  lingual 
nerve,  lying  on  or  internal  to  the  Lingualis  muscle.     It  gives  off  (1)  a  hyoid 


ANATOMY   IN   A   NUTSHELL. 


291 


branch,  which  runs  along  the  upper  border  of  the  hyoid  bone,  (2)  dorsalis 
lingile  branch,  which  passes  upward  under  the  Hyo-glossus  muscle  to  the 
dorsum  of  the  tongue,  (3)  a  sublingual  branch,  which  passes  on  the  Genio- 
hyo-glossus  muscle  to  the  sublingual  gland,  (4)  the  ranine  branch. 

The  fascial  artery  (Plate  CXVI.)  comes  from  the  external  carotid  just  above 
the  origin  of  the  lingual  artery  and  passes  obliquely  upward  under  the  Digastric 
and  Stylo-hyoid  muscles,  it  then  passes  forward  in  a  groove  on  the  posterior 
surface  of  the  submaxillary  gland.  This  much  of  the  artery  is  called  the  cer- 
vical portion.  It  then  passes  upward  over  the  lower  jaw  at  the  anterior  margin 
of  the  Masseter  muscle  to  the  angle  of  the  mouth.  This  portion  of  the  artery 
is  called  the  facial  portion.     It  now  runs  upward  along  the  nose  and  ends  at  the 

PLATE  CXXIII. 


,     fe't^  .    '  UPPER  LOB 

.  Rft&nefl '" 


.    '    k  /Vj-OWER  LOBE J,  f, 

will 


Posterior.  View  of  Lungs. 

inner  canthus  of  the  eye.  This  portion  of  the  artery  is  called  angular  por- 
tion. The  facial  artery  lies  just  under  the  superficial  muscles  and  has  a  very 
tortuous  course. 

The  branches  of  the  facial  artery  given  off  in  the  neck  arc  (I)  [NFERIOR 
or  ascending  palatine,  which  passes  between  the  Stylo-glossus  and  Stylo- 
pharyngeus  muscles  to  the  outer  side  of  the  pharynx  where  it  divides  into  two 
branches,  one  of  which  runs  through  the  Superior  constrictor  muscle  and  the 
other  branch  passes  over  this  muscle.  (2)  The  tonsillar  branch  which 
passes  between  the  Internal  pterygoid  and  Stylo-glossus  muscles  and  after 
piercing  the  Superior  constrictor  passes  to  the  tonsil.     (3)  The  submaxillary 


292 


ANATOMY    IN    A    NUTSHELL. 


branches,  which  are  three  or  four  in  number,  pass  to  the  submaxillary  gland. 
(4)  the  submental  branch,  which  runs  forward  on  the  Mylo-hyoid  muscle 
and  under  the  Digastric  muscle  to  the  symphysis  where  it  divides  into  a  super- 
ficial and  deep  branch  which  pass  over  and  under  the  Depressor  labii  inferioria 
muscle  to  the  lip.  (5)  Muscular  branches  which  pass  to  the  adjacent  muscles. 
The  branches  of  the  facial  artery  given  off  on  the  face  are,  (1)  inferior 
lab]  \i.  which  runs  under  the  Depressor  anguli  oris  muscle  to  the  lower  lip,  (2) 
[NFERIOR  CORONARY  which  runs  in  a  very  tortuous  course  along  the  edge  of 

PLATE  CXXIV. 


COMPLEMENTAl         A|R 

12  0    CUBIC  INCHES 
AIR  THAT    CAN  BE.BUT  SELDOM  IS.TAKEN  IN 


TIDAL         AIR 

20  T0  30      CUBIC  INCHES 
AIR  TAKEN  AND  SENT    OUT    AT    EACH     BREATH 


RESERVE  AIR 

1  0  0  CUBIC  INCHES 
AIR  THAT     CAN  BE.BUT  SELDOM  IS  DRIVEN  OUT 


S     I     D     U    A    L  AIR. 


J0  0         CUBIC  INCHES 


AIR  THAT  CANNOT  BE  DRIVEN  OUT 


Showing  tin:  Capacity  of  the  Luncs. 

the  lower  lip,  (3)  SUPERIOR  CORONARY,  which  is  larger  anil  more  tortuous  even 
than  the  inferior  coronary,  runsalong  the  edge  of  the  upper  lip  andgives  branches 
(a)  to  tIi*  nose,  (b)  the  inferior  artery  of  the  septum,  and  (c)  the  artery  of  the 
ala.  il'  Lateralis  nasi  which  passes  to  the  ala  and  dorsum  of  the  nose.  (5) 
angular  which  passes  to  the  inner  angle  of  the  orbit,  (6)  muscular  which 
pass  to  the  adjacent  muscles. 


ANATOMY    IN    A    NUTSHELL. 


293 


LESSON  LXXXIII. 

The  occipital  artery  (Plate  CXVI)  is  a  branch  from  the  external  carotid 
opposite  the  facial  artery  and  it  passes  under  the  Stylo-hyoid  muscle  and  the 
posterior  belly  of  the  Digastric  muscle.  The  twelfth  cranial  nerve  (hypo- 
glossal) winds  around  it.  This  artery  passes  upward  across  the  spinal  acces- 
sory nerve  and  the  internal  carotid  sheath  to  the  space  between  the  mastoid 
process  of  the  temporal  bone  and  the  transverse  process  of  the  atlas.  It  now 
runs  backward  in  the  occipital  groove  on  the  mastoid  process  and  pierces  the 
origin  of  the  Trapezius  muscle  and  passes  upward  in  a  tortuous  course  to  the 

PLATE   CXXV. 


PLEURA 


Showing  Pleur.e  and  Root  of  the  Lungs. 

vertex,  being  accompanied  by  the  greal  occipital  nerve  in  the  last  part  of  its 
course,  while  the  Complexus  muscle  separates  the  artery  and  nerve  at  the 
beginninu'.  Its  branches  are,  (1)  sterno-mastoid,  which  passes  over  the  hypo- 
glossal nerve  to  the  Sterno-cleido-mastoid  muscle,  (2)  AURICULAR,  which  passes 
to  the  hack  of  the  concha,  and  it  may  send  a  branch  through  the  mastoid  fora- 
men to  the  dura  mater.  (3)  meningeal,  which  passes  through  the  jugular 
foramen  to  the  dura  mater.  |  t)  ARTERIA  PRIN<  EPS  CERVIGIS,  which  descends 
along  the  back  of  the  neck  ami  divides  into  two  branches,  (a)  the  superficial 
<me  which  passes  under  the  Splenius  to  anastomose  with  the  superficial  cervical 
from  the  transversalis  colli,  (b)  the  deep  branch   runs   under   the  Complexus 


294 


ANATOMY    IX    A    NUTSHELL. 


muscle  to  anastomose  with  the  deep  cervical  from  the  superior  intercostal. 
(5)  Muscular  branches  to  the  adjacent  muscles. 

The  posterior  auricular  artery  (Plate  CXVI.)  is  a  branch  of  the  external 
carotid  which  arises  opposite  the  apex  of  the  styloid  process  of  the  temporal 
bone  and  passes  between  the  facial  nerve  and  spinal  accessory  nerve  under  the 
parotid  gland  into  the  groove  between  the  mastoid  process  of  the  temporal 
In  me  and  the  cartilages  of  the  ear  where  it  divides  into  auricular  and  mastoid 
branches.  Its  branches  are  (1)  muscular,  (2)  glandular  (parotid),  (3) 
stylomastoid  which  passes  through  the  stylo-mastoid  foramen  to  (a)  the 
tympanum,  (b)  mastoid  cells,  (c)  semicircular  canals,  and  it  anastomoses  with 
the  tympanic  branch  of  the  internal  maxillary  and  the  petrosal  branch  of  the 
middle  meningeal,  (4)  Auricular  branch  to  back  of  the  ear,  (5)  mastoid  to 
the  scalp  above  and  behind  the  ear. 

The  ascending  pharyngeal  branch  (Plate  CXVI.)  is  the  smallest  and  most 
deeply  seated  of  the  branches  of  the  external  carotid  and  arises  from  near  the 
beginning  of  the  artery  (sometimes  from  the  internal  carotid).     It  passes  up- 

PLATE  CXXVI. 


BRONCHIAL  TUBE 


Air  Cells  of  the  Lungs. 

ward  to  the  base  of  the  skull  on  the  Rectus  capitis  anticus  major  between  the 
pharynx  and  the  internal  carotid  artery.  Its  branches  are  (1)  prevertebral, 
which  passes  to  the  structures  on  the  front  of  the  spine,  (2)  pharyngeal, 
which  pass  to  the  Constrictor  muscles  and  one  of  its  branches  passes  along  the 
Eustachian  tube  to  the  tympanum.  (3)  Meningeal  branches  which  pass  to 
the  dura  mater  through  (a)  middle  lacerated  foramen,  (b)  posterior  lacerated 
foramen,  (c)  anterior  condyloid  foramen. 

The  superficial  temporal  branch  arises  from  the  external  carotid  in  the 
parotid  gland  and  passes  upward  over  the  posterior  root  of  the  zygoma  above 
which  it  divides  into  the  anterior  temporal  and  posterior  temporal.  Its 
branches  are  (1)  small  ones  to  the  parotid  gland.  (2)  articular  ones  to  the 
lower  jaw,  (3)  muscular  ones  to  the  muscles,  (4)  anterior  temporal  which 
runs  forward  to  structures  on  the  frontal  bone,  (5)  posterior  temporal  which 


ANATOMY    IN    A    NUTSHELL. 


295 


runs  upward  and  backward  to  structures  on  the  side  of  the  parietal  bone,  (6) 
transverse  facial  branch  which  crosses  the  Masseter  muscle  and  passes  be- 
tween the  zygoma  and  the  duct  of  the  parotid  gland  (Stenson's)  to  the  side  of 
the  face.  (7)  middle  temporal  which  passes  just  below  the  zygoma  through  the 
temporal  fascia  to  the  muscle,  and  sometimes  it  sends  an  orbital  branch  along 
the  upper  border  of  the  zygoma,  (8)  an  auricular  branch  which  passes  to  the 
external  meatus  and  the  front  of  the  ear. 

PLATE  CXXVII. 


STE  =  '.-'• 


INTERNAL  MAMMARY     VESSELS 
LEFT  PHRENIC  NERVE 
PARIETAL  PLEURA 

VISCERAL  PLEURA 


THORACIC  DUCT 


INTERNAL  MAMMARY     VESSELS 


RIGHT    PHRENIC     NERVE 


PNEUMOGASTRIC  NERVES 
■    OESOPHAGUS 


VENA  AZYGOS  MAJOR 


BODY  OF  DORSAL  VERTEBRA 

A  Transverse  Section  of  the  Pleur.e  Through  Root  of  Lungs. 


LESSON  LXXXIV. 

The  internal  maxillary  artery  (Plate  CXV1)  passes  from  the  external  carotid 
artery  through  the  parotid  gland  to  the  inner  side  of  the  neck  of  the  condyle 
of  the  lower  jaw.  It  now  passes  forward  and  inward  along  the  lower  border  of 
the  external  pterygoid  muscle  and  crosses  the  inferior  dental  nerve  and  is  sit- 
uated between  the  internal  lateral  ligament  and  the  ramus  of  the  jaw.  This 
much  of  the  artery  is  called  maxillary  portion.  It  now  passes  upward  and  for- 
ward over  the  outer  surface  of  the  Internal  pterygoid  muscle  and  this  portion 
of  the  artery  is  called  pterygoid  portion.  It  now  passes  between  the  heads  of 
the  external  pterygoid  muscle  in  the  spheno-maxillary  fossa  where  it  divides 
into  its  terminal  branches.  This  portion  of  the  artery  is  called  spheno-maxillary 
portion. 

The  branches  of  the  maxillary  portion  are  (1)  tympanic  which  passes  up- 
ward behind  the  articulation  of  the  lower  jaw  through  the  Glasserian  fissure 
to  the  ear  drum.  This  artery  together  with  the  Stylo-mastoid  artery  forms  a 
vascular  circle  around  the  ear  drum.      (2)   A   DEEP    auriculae   branch  which 


296 


ANATOMY    IN    A    NUTSHELL. 


passes  to  the  externa]  meatus  and  outer  surface  of  the  drum  (3)  Middlb 
M,A,X",,:u-  BRANCH  which  P^es  upward  between  the  roots  of  the  auriculo* 
temporal  uerve  to  enter  the  foramen  spinosum.  It  uow  divides  into  two  branches 
(a)  a  posterior  one  which  crosses  the  squamous  portion  of  the  temporal  bone. 

PLATE  CXXVIII. 


WGHT      COMMON  CAROTID  ARTERY 
RIGHT  INTERNAL    JUGULAR     VEIN 

RIGHT  VERTEBRAL    VEIN 
RIGHT    SUBCLAVIAN 


R'GHT    INTERNAL      MAMMARr"VEIN 


INFERIOR  THYROID     VEINS 


RIGHT  PULMONARY 


AURICULAR    APPENDIX 


LEFT     COMMON     CAROTID   A 
LEFT   INTERNAL   JUGULAR 
j^EFT    VERTEBRAL     VEIN 

ARTERY 

LEFT  SUBCLAVIAN 


LEFT     INTERNAL 
MAMMARY  VEIN 


LEFT  SUPERIOR 
INTERCOSTAL  VEIN 

ARTERIOUS 


LEFT  PULMONARY 


AURICULAR  APPENDIX 


Arch  of  Aorta  and  Heart. 

(b)  the  :"";,n"r ■  ta  IarSer  and  crosses  the  great  wing  of  the  sphenoid  to  the 

f007e  ^  the  anterior  inferior  angle  of  the  parietal  where  it  divides  into  branches 
*'"•  ''"■  dura  mater  and  inner  surface  of  the  cranium,  it  also  sends  branches  to 
the  Gassenan  ganglion  and  the  dura  mater,  and  a  branch  to  the  facial  nerve 
through   the  hiatus   Fallopii,   this  branch  is  called    petrosal.      It   has   orbital 


ANATOMY    IN    A   NUTSHELL. 


297 


branches  which  pass  through  the  sphenoidal  fissure  and  temporal  branches 
which  pass  through  foramina  in  the  great  wing  of  the  sphenoid  to  the  temporal 
fossa.  (4)  Small  meningeal  may  be  a  branch  of  the  middle  meningeal.  It 
passes  through  the  foramen  ovale  to  the  Gasserian  ganglion.  (5)  Inferior 
dental  passes  with  the  interior  dental  nerve  of  the  fifth  cranial  nerve  into  the 
inferior  dental  canal  to  the  mental  foramen  where  it  divides  into  two  branches, 
(a)  the  incisor  branch  which  passes  to  the  incisor  teeth  and  adjacent  structures, 
and  (b)  mental  branch  which  runs  through  the  mental  foramen  to  the  chin. 
A  mylo-hyoid  which  arises  at  the  inferior  dental  foramen  passes  in  the  mylo- 
hyoid groove  of  the  lower  jaw  to  the  Mylo-hyoid  muscle. 

PLATE  CXXIX. 


Showing  Circulation  of  the  Blood  Through  the  Heart. 

Pterygoid  portion  gives  off  (1)  ANTERIOR  DEEP  TEMPORAL  and  (2)  POSTER- 
IOR deep  temporal,  which  branches  pass  under  the  temporal  muscle  to  the 
temporal  fossa,  (3)  pterygoid  branches  to  the  Pterygoid  muscles.  (4)  M  w- 
BETERIC  branches  which  pass  through  the  sigmoid  notch  to  the  Masseter  mus- 
cle, (5)  BUCCAL  branch  which  passes  between  the  ramus  and  the  Internal  ptery- 
goid muscle  to  the  outer  surface  of  the  Buccinator  muscle. 

The  spheno-inaxillary  portion  gives  off  (1)  alveolar  or  POSTERIOR  dental 
branch,  which  runs  to  (a)  the  tuberosity  of  the  superior  maxillary  hone,  (b) 
posterior  dental  canals,  (c)  alveolar  process,  (d)  gums.  (2)  [nferior  orbital 
which  arises  with  the  posterior  dental  runs  in  the  inferior  orbital  canal  to  the 


298 


ANATOMY    IN    A    NUTSHELL. 


face  and  it  gives  off  in  the  canal  orbital  branches  to  the  orbit  and  anterior  dental 
branches  to  the  anterior  dental  canals,  to  the  antrum  and  teeth.  (3.)  Descend- 
ing palatine  which  d(  Mends  in  the  posterior  palatine  canal  and  runs  forward 
in  a  groove  on  the  hard  palate  then  up  through  the  foramen  of  Stenson.  (4) 
Vidian  branch  passes  backward  through  the  vidian  canal  to  the  pharynx  and 
Eustachian  tube,  sending  a  branch  to  thetypanum.  (5)  Pteh  *  go-palatine  which 
runs  through  the  pterygo-palatine  canal  to  the  pharynx  and  Eustachian  tube. 
(6)  Spheno-palatine  which  runs  through  the  spheno-palatine  foramen  to  the 
Dose.  It  divides  into  external  branches  which  pass  to  the  lateral  walls  of  the 
nose  and  the  nasi  -palatine  branch  which  descends  on  the  septum  to  the  fora- 
men  of  Stenson. 

PLATE  CXXX. 


DECUSSATING    FIBROUS 
TISSUE  OF  VALVE 


FREE  EDGE  OF  VALVE 


CORPUS  ARANTII 

Semilunar  Valves.    (Aortic.) 


LESSON  LXXXV. 

The  First  Three  Cervical  Nerves. 

The  anterior  branch  of  the  First  Spinal  nerve  (suboccipital)  leaves  the  spinal 
canal  in  the  sinus  atlantis  beneath  the  vertebral  artery,  to  the  inner  side  of  the 
Rectus  capitis  lateralis,  and  to  the  outer  side  of  the  upper  articular  process  of 
the  atlas.  From  this  point  it  descends  to  the  front  of  the  transverse  process  of 
the  atlas  and  mutes  with  the  upper  branch  of  the  second  nerve  thus  making 
with  it  the  first,  loop  of  the  Cervical  plexus.      (Plate  (XIII). 

This  first  nerve  receives  a  filament,  from  the  sympathetic  as  it  crosses  the 
foramen  in  the  transverse  process  of  the  atlas.  Prom  the  loop  between  the 
lii-l  and  second  libers  pass  to  the  twelfth  cranial  nerve,  which  unite  with  fibers 
from  it  and  descend  to  form  the  descendens  hypoglossi.  Other  fibers  from  this 
loop  join  the  tenth  cranial  nerve  and  the  sympathetic, also  pass  to  the  Rectus 
capitis  lateral)-  and  the  Rectus  capitus  anticus  major  and  minor.     The  anterior 


PLATE  CXXXI. 


INTERCOSTAL  NODES 


—  INTERNAL  JUGULAR  VEIN 


SUBCLAVIAN  VEIN 


INTERCOSTAL  ARTERY 
VEIN    AND 
NERVE 


.     RECEPJACULUM    'CHYL 

flyf  mx 

mm 

LUMBAR  GLANDS  OR  NODES 

Ijgjn 

,     ;A  l      i  W™^ 
ya|*TH  LUMBAR      Hff 

1 1  p  •  "I 


The  Thoracic  Duct  and  Azygos  Veins. 
'299 


300 


ANATOMY    IN    A    NUTSHELL. 


division  of  the  suboccipital  nerve  sends  filaments  to  the  occipito-atlantal  artic- 
ulation and  the  mastoid  cells  of  the  temporal  hone. 

The  posterior  branch  of  the  suboccipital  nerve  is  larger  than  the  anterior 
branch  and  does  not  divide  into  interna]  and  external  divisions,  (Principle  II,  Page 
26).  h  leaves  the  spinal  canal,  as  does  the  anterior  branch,  in  the  sinus  atlantis 
beneath  the  vertebral  artery,  then   it   passes  backward  into  the  suboccipital 

PLAT!-:  (XXXII. 


THYROHYOID      MEMBRANE 
THYROID  CARTILAGE 

STERNO  THYROID 
CRICOTHYROID  MEMBRANE 

CRIC0- THYROID  MUSCLE 


THYROHYOID  MUSCLE 

t OMO-HTOID 

STERNO-MASTCID 

CRICOID     CARTILAGE 


RIGHT   COMMON       CAROTID  ARTERY 
RIGHT  PNEUMOSASTRIC  NERVE. 
RIGHT       INTERNAL  JUGULAR  VEIN 

btCIION       OF  CLAVICLE 
SECTION  OF    FIFTH    RIB 


OESOPHAGUS 

LEFT     RECURRENT  NERVE 
LEFT    SUSPENSORY     LIGAMENT 


LEFT    INNOMINATE     VEIN 


SECTION  IF  FIRST  niR 


LEFT  INTERNAL    MAMMARY  ARTERY 


Thymus  Gland  of  Fetus. 
t  riangle  and  supplies  the  musch  s  whi<  h  form  the  triangle,  viz..  Superior  oblique, 
Inferior  oblique,  Rectus  ca]  Ltis  posticus  major.  It  sends  a  branch  to  the  Rec- 
ti!- capitis  posticus  minor,  also  to  the  Complexus  which  makes  the  roof  of  the 
triangle.  It  join,-  the  internal  division  of  the  posterior  branch  of  the  second 
cervical  nerve  which  communicate  n  pass<  s  either  through  or  over  the  Inferior 
oblique,  and  it  sometimes  gives  :i  cutaneous  branch  to  the  skin  of  the  lower 


ANATOMY    IX    A    NUTSHELL.  301 

part  of  the  scalp  and  the  upper  part  of  the  neck;  this  cutaneous  branch  accom- 
panies the  occipital  artery  and  communicates  with  thegreat  occipital  and  small 
occipital  nerves.     (Plate  CXII). 

The  superficial  origin  of  the  Second  Spinal  nerve  may  be  as  high  as  a  little 
above  the  posterior  arch  of  the  atlas  or  as  low  as  midway  between  the 
posterior  arch  of  the  atlas  and  spine  of  the  axis.  The  anterior  branch 
of  the  second  cervical  nerve  leaves  the  spinal  canal  between  the  posterior  arch 
of  the  atlas  and  the  lamina  of  the  axis,  behind  the  vertebral  artery  and  in  front 
of  the  posterior  Intertransverse  muscle.  Then  it  passes  to  the  interval  between 
the  Scalenus  medius  and  Rectus  capitis  amicus  major  where  it  divides  into  an 
ascending  branch  which  joins  the  first  cervical  to  make  the  first  loop,  and  one 
or  two  descending  branches  which  join  the  third  cervical  to  make  the  second 
loop  of  the  cervical  plexus.  It  gives  off  (1 )  the  small  occipital  nerve,  which 
runs  upwards  and  backwards  to  the  posterior  border  of  the  Sterno-mastoid, 
where  it  crosses  the  lower  border  of  the  spinal  accessory  nerve  after  which  it 

PLATE  CXXXIII. 

SUPERIOR  CORNU    OF    HYOID  BONE 
/ 


MEDIAN      PORTION      OF 
CRICO-THYROID  MEMBRANE 


CRICC- THYROID 
MUSCLE 


THIRD    RING  OF  TRACHEA 


Thyroid  Cartilage.  (Anterior  View.) 

ascends  along  the  posterior  border  to  the  mastoid  process.  Here  it  pierc< 
deep  fascia  and  crosses  the  upper  pan  of  the  Sterno-cleido-mastoid  into  the 
superficial  fascia  where  it  divides  into  three  branches,  (a)  auricular,  which  runs 
upwards  and  forward  to  supply  the  integum<  m  on  the  inner  and  upper  pan  of 
the  pina,  (b)  a  mastoid  branch  which  is  distributed  to  the  skin  on  the'  base  of 
the  mastoid  pre>cess,  (c)  the-  occipital  branches  which  passover  the  Occipitalis 
muscle  and  are  distributed  to  the'  skin  of  the  scalp.      (  Plate' (X  1 II). 

These  branches  communicate  with  the  great  occipital,  small  occipital. 
great  auricular,  all  of  the  cervical  plexus,  and  with  the  posterior  auricular 
of  the  fifth  nerve-.  (2)  A  branch  helps  to  form  the  greal  auricular,  its  other 
branch  comes  from  the  cervical  nerve.  The  meat  auricular  nerve  passes  with 
the  small  occipital  nerve  to  the  posterior  border  of  the  Sterno-cleido-mastoid, 


302 


ANATOMY    IN    A    NUTSHELL. 


whore  it  leaves  this  nerve  and  passes  across  the  muscle  towards  the  angle  of 
the  mandible.  While  crossing  the  muscle  it  lies  in  the  deep  fascia  almost 
parallel  with  but  behind  the  external  jugular  vein.  It  divides  into  (a)  the 
mastoid  branch  which  is  distributed  to  the  skin  on  the  mastoid  process,  (b)  the 
auricular  branches  which  are  distributed  to  the  integument  on  the  pin  a 
at  Its  upper  part,  some  of  these  branches  are  distributed  to  the  integu- 
ment on  the  outer  surface  of  the  lobule  and  the  outer  surface  of  the  lower  part 
of  the  helix  and  antihelix,  (c)  the  facial  branches  pass  to  the  superficial  lobules 
of  the  parotid  gland  and  the  integument  over  and  in  front  of  the  gland.  In  the 
substance  of  the  gland  they  unite  with  the  cervico-facial  division  of  the  facial 

PLATE  (XXXIV. 


CRICO-THYROID    MEMBRANE 

INFERIOR  CORNU  OF 
THYROID  CARTILAGE. 


MEDIAN      PORTION      OF      THYRO-HYG  0      MEMBRANE  y\ 

SUPERIOR  CORNU    OF 
THYROID     CARTILAGE 


FORAMEN  FOR  SUPERIOR  LARYNGEAL  NERVE 


1 _  MEDIAN     NOTCH  OF 

THYROID    CARTILAGE 


II void  Bone,  Thyroid  and  Cricoid  Cartilages.    (Anterior  View.) 

nerve.  (3)  It  gives  v.  branch  to  help  from  the  superficial  cervical  nerve  which 
com<  -  from  the  second  and  third  cervical  nerves.  It  appears  a  little  below  the 
great  auricular  at  the  posterior  border  of  the  Sterno-cleido-mastoid  and  crosses 
tld-  muscle  lying  under  the  external  jugular  vein,  although  it  may  perforate  it 
or  pass  in  front.  This  nerve  divides  into  ascending  and  descending  branches. 
Tin'  ascending  branches  supply  the  integument  on  the  upper  half  of  the  neck 
as  high  as  the  chin.  It  sends  a  branch  which  accompanies  the  external  jugular 
vein  and  another  which  unites  with  the  facial.  The  descending  branches  sup- 
ply the  integument  <>n  the  lower  half  of  the  neck  as  far  as  the  sternum.  (4) 
One  of  the  communicans  hypoglossi,  and  a  filament  to  the  Sterno- 
CLEIDO-mastoid.  This  filament  communicates  with  the  spinal  accessory  in 
the  substance  of   the   muscle. 


ANATOMY    IN   A    NUTSHELL. 


303 


The  posterior  branch  of  the  second  cervical  nerve  leaves  the  spinal  (anal 

below  the  Inferior  oblique  between  the  posterior  arch  of  the  atlas  and  the 
lamina  of  the  axis.  This  branch  is  larger  than  any  other  posterior  branch  in 
the  cervical  region  and  is  three  or  four  times  as  large  as  the  anterior  branches. 
It  sends  a  twig  to  the  Inferior  and  receives  a  branch  from  the  first  cervical  nerve. 
It  divides  into  a  small  external  division  wihch  supplies  tin-  Complexus  and 
Trachelo-mastoid  and  Splenius  and  gives  a  twig  to  the  Inferior  oblique,  and  a 

PLATE  (XXXV. 


EPIGLOTTIS 


CRICOID    CARTILAGE 


THYROID 

ARYTENO-EPIGLOjTTIDEAN    FOLD^t"^ /~f CARTILAGE      I 

\         k  ^    ^C^-       ^  )  (      i  SANTORINI 

ARYTENOIDEUS     OBLIQUUS 

\        i 
ARYTENOIDEUS     TRANSVERSUS? 

MUSCULAR    PROCESS 

OF 
ARYTENOID  CARTILAGE. 

\  o       ■ ;'  -      &  / 

CR1C0- ARYTENOIDEUS 
'  -x-.,   ■"'  -'//^  POSTICUS 

==«  y 

Thyroid  Cartilages.  (Posterior  View.) 

very  large  internal  division  which  is  the  great  occipital  nerve — the  internal 
division  of  the  posterior  branch  of  the  second  cervical  nerve.  After  this  nerve 
crosses  the  Inferor  oblique  it  pierces  the  Complexus,  the  Trapezius  and  the 
deep  fascia  beneath  the  superior  curved  line  of  the  occipital  bone.  It  joins  a 
filament  from  the  posterior  branch  of  the  third  cervical  nerve  and  ascends  on 
the  back  of  the  head  with  the  occiptial  artery  and  supplies  the  integument  as 
far  as  the  vertex,  communicating  with  the  small  occipital.  It  gives  a  muscular 
branch  to  the  Complexus  and  an  auricular  branch  to  the  back  part  of  the  ear. 
(Plate  CCXVI). 

The  superficial  origin  of  the  third  cervical  nerve  may  be  as  high  as  a  little 
below  THE  POSTERIOR    ARCH   OF  THE   ATLAS  OT   as  low   as  THE  3\  NOTION    OF  THE 

upper  two-thirds  and  lower  third  of  spine  of  \xis.  The  anterior  branch 
of  this  nerve  is  larger  than  the  posterior  one.  (Principle  [I,Page  26).  It  is  also 
larger  than  the  anterior  branch  of  the  second  cervical  nerve  (double  the  size.) 
After  leaving  the  intervertebral  foramen,  it  passes  downward  and  out- 
ward beneath  the  Sterno-cleido-mastoid  and  divides  into  an  ascending  branch 
and  a  descending  one.  The  ascending  branch  joins  the  anterior  branch  of 
second  cervical  nerve,  in  front  of  the  Scalenus  anticus.      The  most  of  the  great 


304 


ANATOMY    IX    A    NUTSHELL. 


auricular,  superficial  cervical,  one  of  the  communicans  hypoglossi,  a  branch  to 
the  supraclavicular  nerves,  a  filament  to  the  phrenic,  and  muscular  branches  to 
the  Levator  anguli  scapula1  and  Trapezius,  and  sometimes  a  branch  to  the 
Scalenus  medius.  all  come  from  this  nerve. 

The  posterior  branch  of  the  third  cervical  nerve  is  smaller  than  that  of  the 
second,  but  larger  than  that  of  the  fourth.  It  divides  at  the  outer  border  of 
the  Semispinalis  colli  into  internal  and  external  divisions.  The  greater  portion 
of  the  internal  division  of  the  posterior  branch  of  the  third  cervical  nerve  is  the 
smallest  or  third  occipital.  The  internal  division  runs  between  the  Complexus 
and  Semispinalis  muscles,  supplying  them,  th<  n  pierces  the  Trapezius  to  supply 
the  integumenl  of  the  back  of  tin  n<  ck.      It  communicates  with  the  great  occipi- 

PLATE  CXXXVI. 


THYRO-EPIGLOTTlDEAN 

LIGAMENT 


CARTILAGO     TRITICEA 


SUPERIOR    CORNU     OF 
THYROID      CARTILAGE 


CARTILAGE    OF    SAN-TOR  Nl 


SCULAR   PROCESS        OF 
RYTEN0I0         CARTILAGE 


INFERIOR  CORNU  OF 
THYROID    CARTILAGE 


Arytenoid  Caktilage  and  Epiglottis. 

tal  nerve  and  supplies  the  skin  of  the  scalp  in  the  region  of  the  external  occipital 
protuberance.  The  external  division  joins  the  posterior  branch  of  the  second 
to  supply  the  Splenius,  Trachelo-mastoid  and  Complexus.     (Plate  CXII.) 


LESSON  LXXXVI. 

<i  i,\  [cal  Plexus.     (Plate  CXIll). 

The  Cervical  plexus  is  formed  by  the  anterior  branches  of  the  first  four 

cervical  nerves.     Each  of  these  four  nerves  receives  a  gray  ramus  communicans 

from  the  si  perior  i  ervical  ganglion.     This  plexus  is  situated  in  the  upper 

part  of  the  side  of  the  neck  opposite  the  four  upper  cervical  vertebrae,  and  upon 


ANATOMY    IN    A    NUTSHELL. 


305 


the  Levator  anguli  scapulae  and  the  Scalenus  medius  muscles  and  under  the 
Sterno-cleiclo-m  ast  o  id . 

The  branches  of  this  plexus  are  superficial  and  deep.  The  superficial 
ones  divide  into  ascending  and  descending,  while  the  deep  divide  into  internal 
and  external. 

The  ascending  branches  are,  (1)  small  occipital.  (2)  great  auricular,  (3) 
transverse  cervical  (this  branch  is  sometimes  called  a  transverse  branch  instead 
of  an  ascending  branch). 

The  descending  branches  are  also  three,  which  come  from  one  main  trunk — 
the  supraclavicular.  These  branches  are,  (1)  suprasternal,  (2)  supraclavicular, 
and  (3)  supra-acromial. 

The  internal  branches  are,  (1)  communicating,  (2)  muscular,  (3)  communi- 
cans  hypoglossi,  (4)  phrenic. 

PLATE  CXXXVII. 


EPIGLOTTIS 


HYOID    BONE 
'CUSHION    OF    EPIGLOTTIS 
THYROID      CARTILAGE 

THYRO-  ARYTENOID 

CRICOID        CARTILAGE 


m 

li|j_FALSE    VOCAL     CORD 
LARYNGEAL    SINUS 

TRUE    VOCAL     CORD 


True  and  False  Vocal  Cords. 

The  external  branches  are,  (1)  communicating,  (2)  muscular. 

The  small  occipital  nerve  (Plate  CCXVI)  is  sometimes  double  and  it  varies 

in  size.  This  nerve  is  derived  from  the  second  cervical  nerve  (and  third)  and 
:it'u  !•  passing  to  the  back  of  the  posterior  border  of  the  Sterno-cleido-mastoid, 
it  passes  along  this  muscle  to  the  mastoid  process  of  the  temporal  bone  where 
it  perforates  the  deep  fascia  and  passes  into  the  superficial  fascia  of  the  scalp. 
It  breaks  up  into  three  branches.  (1)  An  auricular  branch  which  supplies  the 
integument  on  the  inner  and  upper  part  of  the  pina.  (2)  A  mastoid  branch 
which  is  distributed  to  the  integument  on  the  mastoid  process.  (3)  Occipital 
branches  which  are  distributed  to  the  integument  of  the  scalp  and  communi- 
cate with  the  great  occipital,  great  auricular,  and  posterior  auricular  nerves. 

The  great  auricular  nerve  (Plate  CCXVI)  is  derived  from  the  second  and 
third  cervical  nerves  and  after  passing  to  the  posterior  borderof  the  Sterno- 
deido-mastoid,  it  perforates  the  deep  fascia  and  ascends  upon  this  muscle  be- 
neath the  Platysma  to  the  parotid  gland.      This  nerve  lies  almost  parallel  with 


306  ANATOMY    IN    A    NUTSHELL. 

and  behind  the  external  jugular  vein.  It  divides  into  three  branches,  (1) 
auricular,  which  are  three  or  four,  anastomose  with  the  auricular  branches  of 
the  facial  and  pneumogastric  nerves.  It  is  distributed  to  the  integument  of 
the  lobule  and  the  lower  part  of  the  concha.  (2)  A  mastoid  branch  which  is 
distributed  to  the  integument  over  the  mastoid  process.  This  branch  anasto- 
moses  with  the  small  occipital  and  posterior  auricular  nerves.  (3)  The  facial 
branch  crosses  the  parotid  gland  and  supplies  the  integument  covering  the  gland. 
1:  communicates  with  the  seventh  nerve  in  the  gland. 

The  transverse  cervical  nerve  (superficialis  colli)  (Plate  CCXVI)  comes 
from  the  second  and  third  cervical  nerves  and  passes  around  the  posterior  bor- 
der of  the  Sterno-cleido-mastoid  near  its  middle  a  little  below  the  great  auricular 
nerve.  It  now  passes  across  the  neck  beneath  the  integument,  Platysma, and 
externa]  jugular  vein  (sometimes  over  the  vein)  to  spread  out  into  an  ascending 
and  a  descending  branch.  The  ascending  branch  joins  the  cervical  branches 
from  the  facial  nerve  and  supplies  integument  of  the  upper  part  of  the  neck  as 
high  as  the  chin.  The  descending  branch  supplies  the  integument  of  the  lower 
half  of  the  neck  as  far  as  the  sternum. 

The  communicating  branches  of  the  external  division  of  the  deep  branches 
are,  (1)  a  communicating  branch  from  the  second  cervical  nerve  to  the  Sterno- 
cleido-mastoid.  (2)  Those  from  the  third  and  fourth  cervical  nerves  are  dis- 
tributed to  the  Trapezius. 

Muscular  branches  to  (1)  the  Sterno-cleido-mastoid  come  from  the  second 
cervical  nerves  and  joins  the  spinal  accessory  nerve  in  the  substance  of  the 
muscle.  (2)  To  the  Scalenus  medius,  which  comes  from  the  third  and  fourth 
cervical  nerves  and  the  loop  between  them.  (3)  To  the  Levator  anguli  scap- 
ulae, which  comes  from  the  third,  fourth,  and  sometimes  the  fifth  cervical  nerves. 
It  occasionally  comes  from  the  second  also.  (4)  To  the  Trapezius  which 
coin,-  from  the  third  and  fourth  cervical  nerves. 

The  communicating  branches  of  the  internal  division  of  the  deep  branches 
aie.  !l  |  gray  rami  communicantes  from  the  superior  cervical  ganglion  to  each 
of  the  first  four  cervical  nerves,  (2)  a  communicating  branch  to  the  pneumo- 
gastric,  also  one  to  the  hypoglossal,  (3)  communicating  branches,  which  passto 
the  descendens  hypoglossi  from  the  second  and  third  cervical  nerves,  (4)  a 
branch  from  the  fourth  cervical  nerve  to  the  fifth  cervical  nerve. 

.Muscular  branches  pass  to  the  (1)  Rectus  capitis  anticus  minor,  (2)  Rectus 
capitis  anticus  major,  (3)   Rectus  capitis  lateralis,  (4)  Longus  colli. 

Communicans  hypoglossi  is  formed  by  branches  from  the  second  and  third 
cervical  nerves  and  pass  down  on  the  outer  side  of  the  internal  jugular  vein  to 
the  middle  of  the  neck  where  they  join  the  descendens  hypoglossi. 

This  loop  is  called  ansa  hypoglossi.  Branches  are  given  off  from  this  ansa 
to  the  Sterno-hyoid,  Sterno-thyroid,  and  Omo-hyoid. 

The  phrenic  nerve  (internal  respiratory  of  Bell)  is  derived  from  the  third 
fourth,  and  fifth  cervical  nerves,  mainly  from  the  fourth.  As  it  descends  in  the 
neck  it  has  behind  it  the  Scalenus  anticus  and  in  front  of  it  (1)  the  Sterno-clei- 
do-mastoid. (2)  the  posterior  belly  of  the  Omo-hyoid,  (3)  the  transversalis  colli 


ANATOMY    IN    A    NUTSHELL.  307 

vessels,  (4)  the  suprascapular  vessels.  It  now  passes  between  the  first  part  of 
the  subclavian  artery  and  the  subclavian  vein,  and  as  it  passes  into  the  chest 
it  crosses  the  beginning  of  the  internal  mammary  artery.  It  now  passes  ver- 
tically downward  in  front  of  the  root  of  the  lung  between  the  pericardium  and 
the  mediastinal  portion  of  the  pleura.  It  perforates  the  Diaphragm  and  is 
spread  out  on  its  under  surface. 

The  right  phrenic  nerve  lies  on  the  outer  side  of  the  right  innominate  vein 
and  the  superior  vena  cava.  It  is  not  as  long  as  the  left  phrenic  nerve  and  is 
more  vertical  in  direction,  also  seated  deeper. 

The  left  phrenic  nerve  is  longer  than  the  right  phrenic  nerve  for  two  rea- 
sons, (1)  it  has  further  to  go,  because  the  Diaphragm  is  lower  on  the  left  side, 
and  (2)  it  goes  in  a  less  direct  route,  because  the  heart  inclines  to  the  left  side. 
As  it  enters  the  thorax  it  lies  behind  the  left  innominate  vein  and  in  front  of  the 
pneumogastric  nerve,  the  arch  of  the  aorta,  and  the  root  of  the  lung.  The 
comes  nervi  phrenici,  which  is  a  branch  of  the  internal  mammary  artery,  passes 
to  the  phrenic  nerve. 

The  pericardium,  pleura,  (and  peritoneum?)  are  supplied  by  the  phrenic 
nerve.  The  nerve  to  the  subclavius  muscle  sends  a  branch  to  the  phrenic 
nerve,  a  branch  from  the  sympathetic  and  one  from  the  junction  of  the  de- 
scendens  hypoglossi  with  the  cervical  nerves  pass  to  the  phrenic  nerve. 

The  right  phrenic  nerve,  after  it  passes  through  the  Diaphragm,  joins  a 
branch  from  the  solar  plexus  to  form  a  ganglion,  which  gives  branches  to  the 
hepatic  plexus,  the  suprarenal  capsule,  and  the  inferior  vena  cava. 

The  left  phrenic  nerve  has  no  ganglion  upon  it,  but  joins  the  phrenic  plexus. 


LESSON  LXXXVII. 

The  abdominal  wall  is  divided  into  nine  arbitrary  areas  by  four  lines;  first 
a  circle  around  the  body  connecting  the  anterior  superior  spinous  processes  of 
the  crest  of  the  ilia;  a  second  line  drawn  around  the  body  connecting  the  tips 
of  the  ninth  or  tenth  ribs;  the  other  two  lines  are  drawn  at  right  angles  to  these 
from  the  middle  of  Poupart's  ligament,  thus  dividing  the  abdominal  wall  into 
nine  areas.     Plate  CCXXV. 

The  first  one  above  and  on  the  right  side  is  called  the  right  hypochondriac; 
the  middle  one  above  is  the  epigastric; the  third  one  the  left  hypochondriac.  The 
first  one  in  the  middle  row  on  the  left  side  is  the  left  lumbar;  the  next  one  is  the 
umbilical;  and  the  third  is  the  right  lumbar.  The  one  below  the  right  lumbaris 
the  right  iliac  or  inguinal;  the  next  one  in  the  third  row  is  the  hypogastric;  and 
the  third  one  is  the  left  iliac  or  inguinal. 

Epigastric  ("upon  the  stomach").  Hypochondriac  ("under  the  car- 
tilage.")    Hypogastric  ("under  the  stomach.") 

The  right  hypochondriac  contains  the  right  lobe  of  the  liver,  gall-bladder, 
hepatic  flexure  of  the  colon,  and  upper  part  of  the  right  kidney. 

Right  lumbar  contains  the  ascending  colon,  lower  part  of  the  righ.1  kidney. 
and  some  coils  of  the  small  intestine  (ileum.) 

Right  inguinal  (iliac)  contains  the  caecum,  often  the  appendix  vermiformis, 
and  the  end  of  the  ileum. 


PLATE  CXXXVIII. 


ASCENOING  COLON, 


JALL  BLADDER 


LIVER 


PANCREAS 


TRANSVERSE  COLON 


SPLEEN 


SPLENIC     VEIN 


DESCENDING     COLON 


SMALL  INTESTINE 


Showing  the  Entire  Alimentary  Canal  and  the  Portal  Circulation-. 

308 


ANATOMY    IN    A    NUTSHELL.  309 

Epigastric  contains  part  of  the  right  lobe  of  the  liver,  greater  part  of  the 
left  lobe,  part  of  the  gall-bladder  ,  stomach,  middle  and  pyloric  portions,  both 
orifices,  first  two  parts  of  the  duodenum,  duodeno-jejunal  junction,  pancreas, 
except  the  tail,  upper  part  of  the  spleen,  part  of  the  kidneys,  suprarenal  cap- 
sules. 

Umbilical  contains  the  transverse  colon,  part  of  the  great  omentum  and 
mesentery,  transverse  portion  of  the  duodenum,  and  some  coils  of  the  jejunum 
and  ileum,  part  of  both  kidneys  with  ureters,  and  the  receptaculum  chyli. 

Hypogastric  contains  coils  of  the  small  intestine,  the  bladder  in  children, 
or  when  distended  in  adults,  ureters,  the  uterus  during  the  latter  month-  <>t' 
pregnancy,  often  the  caecum,  appendix  vermiformis,  sigmoid  flexure  of  the  colon, 
and  the  upper  part  of  the  rectum. 

Left  hypochondriac  contains  the  fundus  of  the  stomach,  greater  part  of  the 
spleen,  tail  of  the  pancreas,  splenic  flexure  of  the  colon,  upper  part  of  the  left 
kidney,  and  part  of  the  left  lobe  of  the  liver. 

Left  lumbar  contains  the  descending  colon,  part  of  the  omentum,  sigmoid 
flexure,  lower  part  of  the  left  kidney,  and  some  coils  of  the  jejunum. 

Left  inguinal  (iliac)  contains  the  sigmoid  flexure  of  the  colon  and  convo- 
lutions of  the  jejunum  and  ileum. 

Alimentary  Canal.     (Plate  CXXXVIII). 

The  alimentary  canal  is  about  thirty  feet  in  length,  extending  from  the 
mouth  to  the  anus.  It  is  a  musculo-membranous  tube  and  consists  of  the  fol- 
lowing portions:  mouth,  pharynx,  cesophagus.  stomach,  small  intestine  which 
has  the  following  divisions,  (1)  duodenum,  (2)  jejunum,  and  (3)  ileum,  and 
then  comes  the  large  intestine  which  has  the  caecum,  ascending  colon,  hep- 
atic flexure,  transverse  colon,  splenic  flexure,  descending  colon,  sigmoid 
flexure,  and  rectum.  The  accessory  organs  to  the  alimentary  canal  are  the 
teeth,  salivary  glands,  liver,  spleen,  and  pancreas. 

A  viscus  is  any  internal  organ  of  the  body.  The  viscera  are  situated  in 
the  cranium,  thorax,  abdomen,  and  pelvis.  The  Diaphragm  lies  immediately 
above  the  stomach.  All  of  the  canal  above  the  Diaphragm  has  three  coats 
which  are  from  within  outward  the  mucous  membrane,  areolar  tissue  or  sub- 
mucous and  muscular.  That  portion  of  the  canal  which  lies  below  the  1  >ia- 
phragm  has  a  fourth  coat  called  the  serous  membrane,  which  is  external  to 
the  muscular  coat. 

The  teeth  (Plate  CCXXVI)  are  dense  white  structures  firmly  implanted  in 
sockets  in  the  alveolar  processes  of  the  jaw  bones.  Each  consists  of  three  por- 
tions—  A  ROOT  or  PANG,  \  NECK,  and  A  CROWN.  The  teeth  grow  in  two  sets, 
one  in  infancy,  the  other  in  childhood  and  youth.  The  first  set  are  called  tem- 
porary, milk,  deciduous  teeth  and  are  twenty  in  number,  there  being  five  in 
each  lateral  half  jaw,  namely  two  incisors,  one  canine,  and  two  molars.  In 
this  set  there  are  no  bicuspids  and  no  third  molar.  The  bicuspids  of  the  per- 
manent set  take  the  place  of  the  temporary  molars. 

In  the  second  or  permanent  set  there  are  thirty-two  teeth:  eighl  in  each 
lateral    half  jaw,  two  incisors,  one  canine,  two  bicuspids,  and  three  molars. 


310 


ANATOMY    IN    A    NUTSHELL. 


The  arteries  to  the  teeth  are  derived  from  the  inferior  dental  and  from 
the  alveolar  and  infraorbital  branches  of  the  internal  maxillary. 

The  nerves  are  from  the  inferior  dental  branch  of  the  inferior  maxillary 

PLATE  CXXXIX. 


ORIFICE  OF  LACHRYMAL  CANAL 


GROOVE  ON 
ANTERIOR  BORDER  OF 
SEPTAL  CARTILAGE. 


ACCESSORY  CARTILAGE. 


LATERAL  CARTILAGE 
SEPTAL  CARTILAGE 
SESAMOID  CARTILAGF 
ALAR  CARTILAGE 
CELLULAR    TISSUE  OF  ALA 


The  Anterior  and  Posterior  Pillars  of  the  Fauces  and  Cartilages 

of  Nose. 

division  of  the  fifth,  and  also  from  the  anterior  and  posterior  dental  branches  of 
the  superior  maxillary  division  of  the  same  nerve. 

Just  before  the  six-year  molars  are  erupted  from  the  gum,    forty-eight 
teeth  in  various  stages  of  formation  and  retrogression  can  be  recognized  in  the 


ANATOMY    IN    A    NUTSHELL.  311 

two  jaws — twenty  of  the  temporary  set  and  twenty-eight  of  the  permanent 
set.     The  four  wisdom  teeth  at  this  time  are  only  embryonic  buds. 

In  a  sagittal  sectionof  a  tooth  we  see  first  the  enamel  (Plate  CCXXVII)  which 
is  the  hardest  structure  in  the  body,  consisting  of  96.5  per  cent  earthy  and  3.5 
per  cent  animal  matter.  Its  individual  tubules  are  55V0  of  an  inch  in  dia- 
meter. Beneath  the  enamel  is  the  dentine  or  ivory.  The  amount  of  earthy 
matter  is  72  per  cent  and  the  animal  matter  28  per  cent.  Its  tubules  are 
4^70  of  an  inch  in  diameter  and  are  covered  by  the  sheath  of  Neumann,  which 
protects  it  from  the  action  of  acids.  The  cavity  in  the  tooth  is  called  the  pulp 
cavity  and  contains  the  blood  vessels  but  no  lymphatics.  The  tissue  in  the 
cavity  is  called  myxomatous.  The  part  which  surrounds  the  root  as  the  enamel 
surrounds  the  crowm  is  called  the  crusta  petrosa  (Plate  CCXXVII). 

There  are  two  kinds  of  muscles  found  in  the  tongue  (Plate  CXLV)  intrin- 
sic and  extrinsic.  The  intrinsic  are  the  Superior  lingualis,  Inferior  lingualis, 
Transverse  lingualis,  and  Vertical  lingualis.  They  are  all  supplied  by  the 
hypoglossal  nerve.  Some  say  the  Inferior  lingualis  gets  the  Chorda-tympani 
branch  of  the  the  seventh  nerve.  The  extrinsic  muscles  are  the  Genio-hyo- 
glossus,  Palato-glossus,  Hyo-glossus,  Stylo-glossus,  and  Chondro-glossus.  The 
nerve  to  these  is  the  hypoglossal. 

Papilla  means  a  bud,  a  nipple,  a  teat,  a  pimple.  The  lingual  mucous 
membrane  of  the  dorsum  of  the  tongue  is  peculiar  in  several  respects.  It  con- 
sists of  a  layer  of  connective  tissue  forming  a  corium  supporting  special  papilla? 
covered  with  epithelium.  The  corium  is  a  network  in  which  ramify  numerous 
vessels  and  nerves.     The  papillae  are  of  three  kinds. 


LESSON  LXXXVIII. 

1.  Large  circumvallate  ("walled  around")  papillae  seven  in  number  set 
in  an  inverted  V  at  the  back  of  the  tongue  and  shaped  like  truncated  cones  set 
on  end  in  cup-like  depressions,  whence  the  name.     (Plate  CXLIII). 

2.  Middie-sized  fungiform  ("mushroom  shaped")  papillae  scattered  irreg- 
ularly over  the  surface,  forming  rounded  red  eminences  like  mushrooms,  whence 
their  name. 

3.  Small  conical  or  filiform  ("thread-shaped")  papillae  covering  the  an- 
terior two-thirds  of  the  surface,  each  ending  in  a  number  of  little  processes.  It 
is  these  that  are  concerned  in  the  whitish  coating  or  furring  of  the  tongue.  Be- 
sides these  papilla?  there  are  several  other  simple  ones. 

Occupying  the  entire  thickness  of  the  epithelium  of  the  lateral  surface  of 
the  papilla?  is  a  multitude  of  flack-shaped  bodies,  called  tatse-buds.  They  are 
composed  of  two  kinds  of  epithelial  cells,  gustatory  and  sustentacular,  packed 
closely  together.  The  microscopic  structure  of  some  papillae  include  certain 
bodies  called  taste-buds.  Taste-buds  are  scattered  also  over  the  dorsal  surface 
independently  of  papilla?,  and  are  especially  numerous  in  the  posterior  part. 

The  nerves  of  the  tongue  are  in  four  pairs.  1.  The  hypoglossal  is 
the  motor  nerve  to  the  tongue. 


312 


AXATOMr    IX    A    NUTriHKLL. 


2.  The  lingual  (gustatory)  of  trifacial  is  distributed  to  the  anterior  two- 
thirds  of  the  dorsum  of  tongue  and  also  to  sides  of  tongue.  This  nerve  is  one 
of  sensation,  Formerly  it  was  thought  to  be  a  nerve  of  taste,  whence  the  name 
(gustatory,)  which  it  still  retains. 

3.  The  lingual  branch  of  glosso-pharyngeal  is  especially  concerned  in  gus- 

PLATE  CXL. 


FRAENUM  LINGUAL 


DUCT. OF  RiVINUS 


ANTERIOR     BELLr     DIGASTRIC 


Showing  the  Salivary  Glands 


tatlon  (taste)  and  is  distributed  to  the  posterior  one-third  of  dorsum  and  sides 
of  tongue.     (Plate  CXLIII). 

4.  The  function  of  the  lingual  branch  of  the  facial  (Chorda-tympani)  is 
still  in  (p  lest  ion.  Its  distribution  is  about  the  same  as  the  lingual -branch  of  the 
fifth.  Some  say  it  is  a  nerve  of  taste  for  the  anterior  two-thirds  of  the  tongue. 
Others  say  that  it  supplies  the  Inferior  lingualis  muscle.     Still  others  say  that 


ANATOMY    IN    A   NUTSHELL.  313 

the  anterior  two-thirds  of  the   tongue   is  supplied  by   the  glosso-pharyngeal 
through  the  chroda-tympani. 

The  blood  supply  of  the  tongue  is  derived  from  the  lingual,  the  facial,  and 
ascending  pharyngeal  arteries.  The  veins  of  the  tongue  accompany  the  arter- 
ies. 

There  are  two  kinds  of  glands  in  the  tongue.  (Plate  CXL).  the  mucous  and 
serous.  The  mucous  glands  are  found  all  over  the  surface  of  the  mucous  mem- 
brane of  the  tongue.     The  serous  are  found  only  at  the  back  of  the  tongue. 

The  fraenum  linguae  is  a  fold  of  the  mucous  membrane  of  the  mouth  which 
binds  down  the  under  surface  of  the  tongue  and  sometimes  requires  to  be  cut 
from  too  great  restriction  or  from  extension  too  far  forward,  causing  the  sub- 
ject to  be  tongue-tied.     Fraenum  linguae  means  bridle  of  tongue. 

The  dorsum  of  the  tongue  is  convex,  marked  along  the  middle  line  by  a 
raphe,  which  divides  it  into  symmetrical  halves;  this  raphe  terminates  behind, 
about  an  inch,  from  the  base  of  the  organ,  in  a  depression,  the    foramen  caecum, 

The  tongue  is  not  the  only  organ  of  taste  as  taste-buds  are  found  on  the 
back  part  of  the  hard  palate,  on  anterior  part  of  the  soft  palate,  and  to  some 
extent  in  other  parts  of  the  pharynx. 

The  lymphatic  vessels  from  the  tongue  pass  to  one  or  two  small  glands  sit- 
uated on  the  Hyo-glossus  muscle  in  the  sub-maxillary  region,  and  from  thence 
to  the  deep  glands  of  the  neck. 

The  pharynx  (Plate  CXLII)is  bounded  above  by(l)the  base  of  the  sephnoid 
bone  and  (2)  the  basilar  process  of  the  occipital;  behind  by  (1)  the  vertebral 
column.  (2)  Longus  colli  and  (3)  the  Recti  capitis  antici  muscles:  it  is  incom- 
plete in  front  being  bounded  by  the  (1)  internal  pterygoid  plate,  (2)  pterygo- 
maxillary  ligament.  (3)  the  lower  jaw.  (4)  the  tongue,  (5)  the  hyoid  bone,  (6) 
the  thyroid  and  (7)  cricoid  cartilages.  On  the  sides  by  (1)  the  styloid  process 
and  (2)  its  muscles,  (3)  the  common  carotid  and  (4)  internal  carotid  arteries, 
(5)  the  internal  jugular  vein,  (6)  ninth,  (7)  tenth,  (8)  twelfth,  and  (9)  sympa- 
thetic nerves  and  (10)  a  portion  of  the  Internal  pterygoid  muscle.  It  has 
seven  openings,  two  posterior  nares,  two  Eustachian  tubes,  the  oesophagus, the 
mouth,  and  the  larynx.  On  its  posterior  wail  between  the  two  Eustachian 
tubes  there  is  a  collection  of  lymphoid  tissue  similar  to  that  found  in  the  tonsils 
which  forms  the  pharyngeal  tonsil  or  the  third  tonsil.  Above  this  is  the  bursa 
pharyngea,  which  some  authors  think  has  something  to  do  with  the  develop- 
ment of  the  anterior  part  of  the  pituitary  body  and  others  think  it  has  some- 
thing to  do  with  the  development  of  the  third  tonsil. 

The  pharnyx,  the  throat,  technically  the  joint  opening  of  the  gullet  and  the 
windpipe,  is  a  musculo-membranons  pouch  situated  at  the  back  of  the  nasal 
cavities,  mouth  and  larynx  and  extending  from  base  of  skull  to  the  cricoid  car- 
tilage. It  is  about  five  inches  long.  It  i-  widest  (nearly  one  inch  and  a  half1) 
in  the  upper  pharyngeal  portion,  and  narrow  above  and  below,  having  its  least 
diameter  (half  an  inch)  at  its  junction  with  the  gullet.  Ventro-dorsally  its 
measurement  is  everywhere  small,  only  opposite  the  mouth  being  more  than 
four-fifths  of  an  inch.     It  is  a  cavity  situated  in  front  of  the  upper  live  cervical 


314 


ANATOMY    IN    A    NUTSHELL. 


vertebrae.  The  pharynx  also  belongs  to  the  respiratory  system.  The  middle 
segmenl  of  the  pharynx  is  common  to  the  alimentary  and  respiratory  systems, 
and  the  tracts  followed  by  the  food  and  air  cross  obliquely  in  it.  The  pharynx 
lias  three  tunics,  the  mucous,  areolar,  and  muscular. 

PLATE  CXI. I. 


TENSOR      PALATI. 

EUSTACHIAN  TUBE 

LEVATOR     PALATI 
PTERYGOMANDIBULAR  LIGAMENT 
STYLO-PHARYNGEUS. 

9TH  NERVE-GLOSS O-PHARYNGEAL 
"STYLO-GLOSSUS 


MYLO-HYOID 
HYO-GLOSSUS 

STYL0-HYOID 
D   I  GASTRIC 


THYROID  CARTILAGE 


STYLOHYOID  LIGAMENT 


HYPOGLOSSAL 


SUPERIOR    LARYNGEAL    N. 


CURRENT  LARYNGEAL  NERVE 


Showing  the  Muscles  of  the  Pharynx. 

The  muscles  of  the  pharnyx  (  Plate  CXLI)  arc  Superior  constrictor,  Middle 
constrictor,    Inferior    constrictor,    Stylo-pharyngeus,    Palato-pharyngeus,    and 

Salpingo-pharyngeus.     The  Constrictors   are  supplied   by   branches    from  the 
pharyngeal    plexus.      The    Stylo-pharyngeus   by   the  glosso-pharyngeal  nerve 


ANATOMY   IX   A    NUTSHELL.  315 

and  the  Inferior  constrictor  gets,  in  addition,  branches  from  the  external  laryn- 
geal nerve  and  the  recurrent  laryngeal.  The  Palato-pharyngeus  probably 
gets  its  nerve  supply  from  the  internal  branch  of  the  spinal  accessory,  whose 
fibers  are  distributed  along  with  certain  branches  of  the  pneumogastric  through 
the  pharyngeal  plexus. 

The  pharyngeal  plexus  is  formed  by  branches  of  the  vagus,  sympathetic  and 
glossc-pharyngeal.  It  supplies  the  muscles  and  mucous  membrane  of  the 
pharynx. 

The  blood  supply  of  the  pharynx  is  from  the  superior  thyroid  branches, 
ascending  pharyngeal,  pterygopalatine,  and  descending  palatine.  The  first 
two  are  branches  of  the  external  carotid,  the  last  two  are  branches  of  the  internal 
maxillary. 

The  sinus  of  3Iorgagni  is  a  space  at  the  upper  and  back  part  of  the  Superior 
constrictor  of  the  pharynx,  just  under  the  base  of  the  skull  where  the  muscular 
fibers  of  the  Constrictor  are  deficient,  the  pharynx  being  consequently  walled 
in  behind  by  its  own  aponeurosis.  Here  the  Eustachian  tube  opens  into  the 
pharynx,  one  on  each  side. 


LESSON  LXXXIX. 

The  tonsils  (Plate  CXXXIX)  are  two  prominent  oval  bodies  situated  in  there- 
cesses  formed  one  on  each  side  of  the  fauces,  between  the  anterior  and  pos- 
terior palatine  arches.  They  are  composed  of  lymphoid  follicles,  surrounded  by 
less  dense  lymphoid  tissue  arranged  around  the  walls  of  crypts.  They  lie  near 
the  internal  carotid  artery.  The  blood  supply  is  from  the  dorsalis  lingua?  from 
the  lingual;  ascending  pharyngeal  from  external  carotid;  ascending  palatine 
from  facial ;  tonsillar  from  facial :  descending  palatine  from  internal  maxillary. 
(Plate  CXVI) The  veins  of  the  tonsil  form  a  plexus  which  lies  upon  the  outer  side 
of  the  gland  and  opens  externally  into  the  pharyngeal  plexus.  The  nerves  to 
the  tonsils  come  from  the  fifth  by  means  of  Meckel's  ganglion  and  from  the 
glosso-pharyngeal  nerve. 

Steno's  duct  (Stenson's)  (Plate  CXL)  is  a  duct  of  the  parotid  gland  convey- 
ing saliva  into  the  mouth;  so  named  from  the  Danish  anatomist,  Nicholas  Steno, 
of  Copenhagen  (1638-86).     This  duct  is  also  called  parotid  duct. 

Wharton's  duct  named  from  Thomas  Wharton,  an  English  physician,  1656. 
The  duct  of  the  submaxillary  gland,  conveying  saliva  into  the  mouth,  about 
two  inches  long,  opening  on  a  papilla  at  the  sideof  the  fraenum  linguae,  or  bridle 
of  the  tongue. 

The  ducts  of  Rivinus  are  those  ducts  of  the  sublingual  gland  which  open 
apart  from  one  another  and  from  Wharton's  duct. 

The  duct  of  Bartholin  is  one  of  the  ducts  of  the  sublingual  gland  running 
along  side  of  Wharton's  duct,  and  opening  into  it  or  close  to  its  orifice  into  the 
mouth. 

Thehardpalate(PlateCC.WYIII)  isin  the  roof  of  the  mouth  and  is  formed  by 
the  palate  processes  of  the  superior  maxillary  and  palate  bones.  The  soft  palate 
is  a  movable  fold  suspended  from  the  posterior  bonier  of  the  hard  palate,  form- 


ANATOMY    IX    A    NUTSHELL 


•  ,u  incomplete  septum  between  the  mouth  and  pharynx.  The  muscles  oi 
the  sofl  palate  are  the  Levator  palati,  Tensor  palati,  AzygOs  uvula,  Palato- 
glossus and  Palato-pharyngeus.  The  Tensor  palati  is  supplied  by  the  Otafl 
ganglion.     The  remaining  muscles  of  this  group  are  in  all  probability  supplied 

PLATE  CX  LI  I 


PROBE     PASSED  FROM  FRONTAL^SINUS 
THROUGH  INFL'NDIBULUM 

Hi 

0PE\;NGS  OF  POSTERIOR  ETHMO 


VESTIGULE 


Sagittal  Section  of  the  Head  and  Neck  Showing  the  Pharynx. 


by  the  internal  branch  of  the  spinal  accessory,  whose  fibers  are  distributed  along 
with  certain  branches  of  the  pneumogastic  through  the  pharyngeal  plexus. 

The  isthmus  of  the  fauces  is  called  the  throat.  The  anterior  pillars  of  the 
fan.-.-  art  in:. Me  by  two  muscles  covered  with  mucous  membrane,  the  two  Pala- 
to-glossi,  and  the  posterior  pillars  are  made  by  the  two  Palato-pharyngei. 


ANATOMY    IN    A  NUTSHELL.  317 

The  next  part  of  the  alimentary  canal  is  called  the  oesophagus  (Plate CXLVI) 
which  extends  from  the  spinous  process  of  the  sixth  cervical  vertebra  to  the 

cardiac  end  of  the  stomach  opposite  the  spinous  process  of  the  ninth  dorsal.  It 
consists  of  three  coats,  an  outer  or  muscular,  a  middle  or  areolar,  and  an  internal 
or  mucous.  All  of  the  alimentary  canal  above  the  diaphragm  has  three  coats, 
and  all  below  it  has  four  coats,  these  three  just  mentioned  and  a  serous  coat  or 
peritoneum. 

The  oesophagus  (Plate  CXLVI)  in  the  neck,  is  boundeb!  in  front  by  the 
trachea,  the  thyroid  gland,  and  the  thoracic  duct.  On  each  side  by  the  common 
carotid  artery,  the  lateral  part  of  the  lobes  of  the  thyroid  gland,  and  the  re- 
current laryngeal  nerve.     Behind  by  the  vertebral  column  and  the  Longus  colli. 

In  the  thorax  it  is  bounded  in  front  by  the  trachea,  arch  of  the  aorta,  left 
common  carotid  artery,  left  subclavian  artery,  left  bronchus,  pericardium,  and 
Diaphragm.  Behind  by  the  vertebral  column,  Longus  colli,  vena  azygos  minor, 
right  intercostal  arteries,  thoracic  duct,  aorta,  and  the  abdominal  aorta.  On 
the  right  side  by  the  right  lung  and  pleura,  vena  azygos  major,  and  the  thoracic 
duct.  On  the  left  side  by  the  left  lung  and  pleura,  and  thoracic  aorta.  The 
left  pneumogastric  and  right  pneumogastric  surround  the  oesophagus,  the  right 
being  situated  behind  it  and  the  left  in  front,  forming  the  plexus  of  Gula?  in  the 
muscular  coat. 

The  muscular  coat  consists  at  first  of  three  perpendicular  bands,  the  anterior 
one  being  attached  to  the  posterior  part  of  the  cricoid  cartilage  and  the  lateral 
ones  being  continuous  with  the  Inferior  constrictor  of  the  pharynx.  These 
three  bands  gradually  blend  and  make  a  circular  muscular  band  around  the 
oesophagus.  The  next  coat  is  the  circular  coat  which  is  continuous  with  the 
fibers  of  the  Inferior  constrictor  and  at  the  upper  part  of  the  oesophagus  they  are 
parallel  and  at  the  lower  part  they  are  parallel,  but  in  the  intermediate  portion 
they  are  oblique.  The  upper  ones  are  striped  or  voluntary  muscles,  while  the 
lower  ones  are  involuntary.  The  glands  of  the  esophagus  are  compound  race- 
mose glands  which  empty  by  long  tubes  on  the  mucous  membrane. 

The  oesophagus  (carrying  eatables)  or  gullet  is  a  tube  connecting  the  pharynx 
and  stomach.  It  is  about  ten  inches  long.  The  blood  supply  is  from  the  Infer- 
ior thyroid  which  comes  from  the  thyroid  axis  of  the  subclavian;  branches  from 
t  he  d(  sc<  oding  thora<  ic  aorta ;  and  from  the  gast  i  ic  branches  of  the  coeliac  axis 
of  abdominal  aorta.  The  nerve  supply  is  from  th<  pneumogastric  and  sympa- 
thetic. They  form  a  plexus  in  which  are  groups  of  ganglion-cells  between  the 
two  layers  of  the  muscular  coats,  and  also  a  second  plexus  in  the  submucous 
tissue. 


318  ANATOMY    IN    A    NUTSHELL. 

LESSON  XC. 

The  stomach  (  Plate  CXLYI)  is  the  most dilated  and  most  distensible  part  of 
the  alimentary  canal.  It  occupies  parts  of  the  left  hypochondriac  and  epigas- 
tric regions  of  the  abdomen,  immediately  within  the  abdominal  walls  below  the 
diaphragm  and  partly  under  the  liver  to  the  right  of  the  spleen  and  above  the 
transverse  colon.  In  form  it  is  irregularly  conoidal  and  curved  upon  itself. 
When  moderately  distended  it  is  about  twelve  inches  long  and  four  inches  wide; 
it  weighs  three  or  four  ounces.  The  size,  shape,  and  hence  anatomical  rela- 
tion.^, differ  greatly  in  different  states  of  distension.  It  is  somewhat  like  a  pear 
with  the  large  end  up  and  the  small  end  bent  side  wise  to  the  right.  The  fundus 
or  splenic  end  is  connected  to  the  spleen  by  the  gastro-splenic  omentum.  We 
niiuht  mention  that  an  omentum  is  a  special  mesentery  connecting  the  stomach 
with  the  liver,  spleen,  and  colon  respectively.  The  one  that  connects  it  to  the 
spleen  is  called  gastro-splenic  omentum.  The  one  that  connects  it  to  the  liver 
is  called  the  gastro-hepatic  omentum,  and  the  one  to  the  colon  is  called  the 
gastro-colic  omentum.  The  pylorus  or  lesser  end  lies  near  the  cartilage  of  the 
eighth  rib,  in  contact  with  the  under  surface  of  the  liver.  The  stomach  has  two 
curves,  a  greater  and  a  lesser.  The  greater  is  convex  and  is  connected  to  the 
colon  by  the  gastro-colic  omentum.  The  lesser  one  is  concave  and  is  connected 
to  the  liver  by  the  gastro-hepatic  omentum,  and  to  the  Diaphragm  by  the  gas- 
trophrenic ligament.  The  oesophageal  or  cardiac  orifice  is  situated  between 
the  fundus  and  the  lesser  curvature. 

The  pyloric  (janitor)  is  situated  at  the  extreme  right  and  is  more  anterior 
in  position  than  the  cardiac  orifice.  The  stomach  has  four  tunics,  serous,  mus- 
cular, areolar  or  submucous,  and  mucous.  The  serous  coat  (peritoneum)  en- 
closes the  stomach  between  two  layers,  derived  from  the  lesser  omentum.  Tha 
lesser  omentum,  omentum  minimus,  or  gastro-hepatic  is  a  single  fold  (two 
layers)  of  peritoneum,  extending  between  the  transverse  fissure  of  the  liver  and 
the  lessee  curvature  of  the  stomach.  It  might  be  well  to  explain  the  greater 
omentum,  omentum  magnus  or  gastro-colic  omentum  also  called  epiploon,  It 
is  the  largest  of  all  peritoneal  duplications,  and  consists  of  four  layers  of  peri- 
toneum attached  to  the  greater  curvature  of  the  stomach  and  to  the  transverse 
colon,  whence  it  is  looped  down  freely  upon  the  intestines,  forming  a  great  flap 
or  apron.  The  muscular  coat  has  two  distinct  layers — an  outer,  longitudinal, 
and  an  inner,  circular.  Besides  these  two  distinct  layers  some  oblique  fasci- 
culi are  found  internal  to  the  circular.  The  areolar,  submucous,  also  called 
vascular,  is  loose,  and  its  meshes  are  largely  occupied  with  the  vessels  and  nerves 
going  to  and  from  the  coats  between  which  it  lies.  The  mucous  coat  is  thrown 
into  irregular  Longitudinal  folds  called  rugae.  The  rugse  invade  the  mucous 
and  submucous  coats. 

There  are  two  kinds  of  glands  in  the  stomach,  the  cardiac  or  proper  gastric 
glands   also  called  peptic  (digest),  and  the  pyloric  glands 

The  aerve  supply  to  the  stomach  is  the  right  and  left  pneumogastric  and 
branches  from  the  solar  plexus  of  sympathetic  nerves. 

The  blood  supply   to    stomach  (Plate  CXLVIII)  is  from  the  coeliac  axis. 


ANATOMY    IN    A    NUTSHELL. 


319 


(1)  the  gastric  artery  which  runs  along  the  lesser  curve  from  left  to  right  anas- 
tomosing with  the  (2)  pyloric  branch  of  the  hepatic.  Along  the  greater  curve 
run  the  (3)  right  and  (4)  left  gastro-epiploic  arteries,  anastomosing  at  the 
middle  of  the  border,  the  left  being  a  branch  of  the  splenic,  the  right  a  branch  of 
the  hepatic  through  the  gastro-duodenalis  artery.  The  stomach  also  receives 
branches  from  the  splenic  (5)  vasa  brevia  at  the  fundus.  The  blood  of  the 
stomach  is  returned  into  the  portal  vein;  the  right  gastro-epiploic  vein  opens 
into  the   superior  mesenteric,  the  left  into   the  splenic.     The   lymphatics   are 

PLATE  CXLIII. 

PHARYNX 
.■.••■•.•:-.:,-;<i''i??'i::^yj 


Wm 


\'  v£ 


■*'*  ■■:';  ii'-'-T  Hi^t  ■'■St- 

The  Dorsum  of  the  Tongue. 

numerous;  they  consist  of  a  superficial  and  deep  set  which  pass   through    the 
lymphatic  glands  forward  along  the  two  curvatures  of  the  stomach. 

The  stomach  has  above  it,(Plate  CXLIX),the  Diaphragm,lesser omentum, 
and  the  liver;  in  front,  the  Diaphragm,  the  liver,  and  the  anterior  abdominal 
wall;  below  it,  the  great  omentum,  the  transverse  colon,  and  the  gastros-plenic 
omentum;  behind  it,  the  kidney,  suprarenal  capsule,  pancreas  and  spleen,  which 
are  called  the  "Big-four,"  The  "Little-four"  which  are  the  great  vessels,  solar 
transverse  meso-colon,  and  crura  of  the  diaphragm  aie  also  behind  it. 


320  ANATOMY    IN    A    NUTSHELL. 


LESSON  XCI. 


The  first  part  of  the  small  intestine  is  called  the  duodenum;  the  literal 
meaning  of  which  is  twelve  finger  lengths,  hut  this  is  not  twelve  finger  lengths  or 
twelve  finger  breadths.  It  has  a  mesentery.  The  duodenum  may  consist  of 
five  portions,  the  transverse,  descending,  inferior  transverse,  ascending,  and 
the  flexure — duodeno-jejunal  flexure.  It  has  glands  in  it  called  Brunner's 
glands  or  duodenal  glands. 

The  next  part  of  the  small  intestine  is  called  jejunum,  and  the  third  part  is 
called  ileum.  The  first  portion  consists  of  about  three-fifths  of  it  below  the 
duodenum,  and  the  ileum  about  two-fifths.  The  glands  in  the  ileum  are  called 
Peyer's  pan  lies  winch  are  about  thirty  in  number;  the  intestine  is  thinner  here 
than  in  other  parts.  The  small  intestine  straightened  out  would  be  in  the  shape 
of  a  slender  cone,  with  the  base  corresponding  to  the  stomach  end,  and  its  apex 
corresponding  to  the  point  where  it  joins  the  caecum. 

The  large  intestine  consists  of  first,  the  cecum  which  may  be  various  shapes 
and  is  partly  covered  with  peritoneum;  the  next  part  is  the  ASCENDING  COLON 
which  in  27  per  cent  of  casts  is  covered  with  peritoneum;  it  is  about  eight  and 
one-half  inches  long.  The  next  portion  is  the  hepatic  flexure  which  joins 
the  ascending  with  the  transverse  colon.  This  transverse  colon  is  about 
twenty  inches  long,  and  is  covered  with  peritoneum.  The  next  part  is  the 
splenic  flexure  which  joins  the  transverse  with  the  descending  colon.  The 
descending  colon  is  about  nine  inch's  in  length  and  in  37  per  cent  of  cases  is 
covered  with  peritoneum.  The  next  part  is  called  the  sigmoid  flexure,  which 
is  about  fourteen  inches  in  length.  The  last  part  is  the  rectum  (which  means 
straight):  it  is  not  straight  but  relatively  straight  compared  with  the  rest  of 
the  alimentary  canal. 

The  glands  of  the  large  intestine  are  less  numerous,  and  lie  along  the 
vascular  arches  of  the  arteries  or  even  upon  the  gut  itself;  they  are  fewest  along 
the  transverse  colon. 

The  lymphatic  vessels  of  the  large  intestine  form  two  sets,  viz., those  of  the 
caecum,  ascending  and  transverse  colon, which  pass  through  their  proper  glands 
to  the  mesenteric  glands;  and  those  of  the  descending  colon,  sigmoid  flexure, 
and  rectum   which  pass  to  the  lumbar  glands. 

The  small  intestine  (intestinum  tenue,)  (Plate  CL VI) , extends  between  the 
stomach  above  and  the  large  intestine  below.  Its  average  length  is  about 
twenty-two  fe<  t.  It  may  be  as  many  as  thirty-four  feet  or  as  few  as  eight  feet 
in  length.  [ts  diameter  diminishes  in  size  from  about  two  inches  above  to  less 
than  oik  inch  below.  It  is  to  a  huge  extent  within  the  area  bounded  by  the 
colon,  occupying  the  umbilical  and  hypogastric  regions  and  the  adjacent  por- 
tions of  the  lumbar.  It  has  four  coats  which  correspond  in  general  arrange- 
ment and  character  to  those  of  the  stomach.  They  are  the  serous,  muscular, 
areolar,  and  mucous.  The  divisions  of  the  small  intestine  are  the  duodenum 
(twelve  finger  intestine,)  jejunum  (empty  intestine.)  and  ileum  (curved  or 
twisted  intestine.)     The  villi  are  small  projections  on  the  mucous  membrane  of 


ANATOMY    IN    A    NUTSHELL. 


321 


the  small  intestine,  which  are  so  numerous  as  to  give  it  a  velvety  appearance. 
Thev  are  from  four  to  ten  millions  in  number.  They  collectively  constitute  the 
beginning  of  the  absorbent  or  lacteal  vessels  of  the  intestine. 

The  valvular  eonniventes  are  transverse  folds  of  the  mucous  membrane  and 
underlying  tissues  found  throughout  a  large  extent  of  the  small  intestine. 
Their  use  is  probably  to  retard  somewhat  the  passage  of  alimentary  mass,  and 
and  at  the  same  time  to  offer  a  greater  surface  for  absorption. 

Lieberkuhn  glaxds,  crypts,  are  the  simple  or  solitary  glands  of  the  in- 
testine, also  in  large  intestine.  Brunner  glands  (so-called  from  J.  K. 
Brunner,    1653-1727).    sometimes    called    duodenal    glands,     are    small    com- 

PLATE  CXLIV. 


Circum vallate  Papill.e. 


pound  glands  of  the  duodenum  and  upper  part  of  the  jejunum,  embedded  in  the 
submucous  tissue,  opening  by  minute  orifices  into  the  lumen  of  the  intestine. 

Then  there  are  the  solitary  lymph-nodules,  which  are  more  frequently 
called  solitary  glands,  though  no  more  entitled  to  the  name  than  the  nodes 
which  occur  in  the  course  of  lymphatic  vessels,    having  no  secretive  apparatus. 

Beyer's  Patches  are  found  in  the  lower  ileum.  They  are  oval,  are  from 
one-half  to  three  inches  in  length,  and  about  an  inch  in  breadth.  They  are 
placed  in  long  axis  of  the  bowel.  These  patches  were  named  after  J.  K.  Peyer, 
a  Swiss  anatomist  (1653-1712).  A  lesion  of  these  patches  is  one  of  the  most 
constant  signs  of  typhoid  fever. 


LESSON  XCII. 

The  small  intestine  receives  the  blood  from  the  superior  mesenteric  artery, 
and  a  branch  coming  indirectly  from  the  hepatic,  the  superior  pancreatico- 
duodenalis.  The  superior  mesenteric  runs  between  the  layers  of  the  mesentery 
and  gives  off  twelve  or  fifteen  branches  running  downwards  and  to  the  left 
(vasa  intestini  tenuis,)  which  break  up  ami  form  a  series  of  arches, finally  encir- 
cling the  intestine  as  small  branches.      It  also  gives  off    a  small  branch  at  the 


322  ANATOMY   IN   A    NUTSHELL. 

beginning,  the  inferior  pancreatico-duodenalis,  which,  with  the  superior  pan- 
creatico-duodenaJis,  forms  as  arch  which  lies  in  the  concavity  of  the  duodenum 
and  which  supplies  it. 

The  blood  is  returned  by  means  of  the  superior  mesenteric  vein  which, 
with  the  splenic  forms  the  portal  vein. 

The  lymphatics  form  a  continuous  series,  which  is  divided  into  two  sets — 
thai  of  the  mucous  membrane  and  that  of  the  muscular  coat.  The  lymph- 
vessels  of  both  sets  form  a  copious  plexus  and  end  in  the  mesenteric  lacteals. 

The  nerve  supply  of  the  small  intestine  is  by  means  of  the  superior  mesenteric 
plexus,  which  is  continuous  with  the  lower  part  of  the  solar  plexus.  The 
branches  follow  the  blood  vessels,  and  finally  form  two  plexuses,  one  (Auer- 
bach's)  which  lies  between  the  muscular  coats;  and  another  (Meissner's)  in  the 
submucous  coat. 

The  follicles  of  Lieberkuhn  are  found  in  the  large  and  small  intestine. 

The  large  intestine  (intestinum  crassum)  is  about  a  quarter  as  long  as  the 
small  intestine.  It  is  called  large  on  account  of  its  diameter,  being  about  two 
and  a  half  inches  in  its  broadest  part.  It  begins  at  the  right  and  lower  portion 
of  the  abdomen,  passes  upward  and  backward  to  the  under  surface  of  the  liver, 
thence  across  the  belly  to  the  spleen,  from  this  point  downward  and  forward  to 
the  left  and  lower  part  of  the  abdomen,  here  it  makes  a  number  of  curves,  and 
finally  plunges  into  the  pelvis  at  its  back  part,  and  ends  close  to  the  perineum, 
near  the  inner  opening  of  the  anal  colon.  Its  divisions  are  the  caecum,  ascend- 
ing, transverse,  descending  colon,  sigmoid  flexure,  and  rectum. 

The  glands  of  the  small  intestines  or  mesenteric  glands  (100-150)  lie  between 
the  layers  of  the  mesentery  among  the  meshes  formed  by  the  superior  mesenteric 
vessels,  their  size  varying  from  that  of  a  pea  to  that  of  a  small  almond.  They 
are  largest  and  most  numerous  near  the  duodenum  and  the  ileo-colic  valve. 

The  \csscls  of  the  small  intestine  or  lacteals,  are  of  two  kinds,  viz.,  super- 
ficial, placed  between  the  layers  of  the  muscular  coat,  or  between  the  muscular 
ami  peritoneal  coats,  and  running  longitudinally;  and  deep,  placed  in  the  sub- 
mucous tissue  and  running  transversely  around  the  gut  with  the  mesenteric 
vessels.  They  pass  between  the  layers  of  the  mesentery  and  then,  in  two  or 
three  large  trunks,  into  the  thoracic  duct. 

Tho  caecum  lies  in  the  right  iliac  fossa;  from  this  point  the  ascending  colon 
passes  to  the  liver.  Here  it  forms  the  hepatic  flexure,  then  passes  transversely 
across  the  belly  below  the  stomach,  and  here  the  splenic  flexure  is  formed, 
then  ii  passes  downward,  forming  the  descending  colon.  In  the  left  iliac  fossa  it 
forms  the  sigmoid  flexure,  and  then  passes  through  the  pelvis  as  the  rectum. 

The  large  intestine  has  four  coats  with  the  same  arrangement  as  the  stomach 
and  small  intestine:  serous,  muscular,  areolar,  mucous. 

The  large  intestine  has  the  crypts  of  Lieberkuhn  and  solitary  glands.  It 
has  no  villi,  no  valvulse  conniventes,  no  glands  of  Brunner,  no  patches  of  Peyer. 

The  vermiform  appendix  is  a  blind  process  given  off  from  the  caecum,  vary- 
in  man  from  three  to  six  inches.      (Plate  CLLY.) 

The  opening  of  the  small  intestine  into  the  large  is  provided  with  promi- 
nent lips  which  project  into  the  cavity  of  the  latter,  and  oppose  the  passage  of 


ANATOMY    IN    A    NUTSHELL. 


323 


matter  from  it  into  the  small  intestine,  while  they  readily  allow  of  a  passage  the 
other  way.     This  is  the  ileo-caeeal  valve  or  valve  of  Bauhini. 

The  large  intestine  is  supplied  with  blood  by  the  branches  of  the  superior 

PLATE  CXLV. 


LIFT  MASTOID  PROCESS 


GUST' 


TWELFTH  NERVE. 


INT.    LARYNGEAL    N. 


HYOIDBONE 

The  Extrinsic  Muscles  of  the  Tongue. 

mesenteric  and  inferior  mesenteric  arteries,  while  it  also  receives  a  blood  sup- 
ply from  the  internal  iliac  at  the  rectum.  The  vessels  form  a  contiunous  series 
of  arches  from  the  caecum,  where  the  vasa  intestini  tenuis  anastomose  with 
the  ileo-colic,  the  first  branch  of  the  superior  mesenteric  given  to  the  huge  in- 
testine. The  blood  supply  of  the  rectum  is  from  the  inferior  mesenteric  by  the 
Superior  hemorrhoidal,  from  the  internal  iliac,  by  the  middle  hemorrhoidal,  and 
from  the  internal  pudic  by  the  inferior  hemorrhoidal.  The  vessels  at  the  lower 
end  of  the  rectum  assume  a  longitudinal  direction,  communicating  freely  at  the 
anus  and  less  freely  above.  The  blood  of  the  large  intestine  is  turned  into  the 
portal  vein  by  means  of  the  superior  mesenteric  and  inferior  mesenteric  veins. 
At  the  rectum  a  communication  is  se1  up  between  the  systemic  and  portal  sys- 
tem of  veins,  since  some  of  the  Mood  of  that  pari  of  the  intestine  is  returned  into 
the  internal  iliac  veins.  In  the  lower  end  of  the  rectum  the  vein.-,  like  the  arter- 
ies, are  arranged  longitudinally.  This  arrangement  is  called  the  hemorrhoidal 
plexus. 


324  ANATOMY    IN    A    NUTSHELL. 

The  nerves  and  lymphatics  differ  in  no  particular  from  those  of  the  small 
intestine. 

The  rectum  (intestinum  rectum)  extends  from  the  sacro-iliac  joint  to  the 
amis.  It  better  deserves  the  name  rectum  (straight,)  when  we  say  it  begins  at 
the  front  of  the  third  sacral  vertebra,  for  then  it  is  nearer  straight.  It  has  the 
same  four  coats  that  the  intestine  has.  Its  walls  are  thicker  than  those  of  the 
colon.  The  muscular  coat  and  mucous  coat  differ  from  those  of  the  outer  por- 
tions of  the  canal.  The  peritoneum  of  the  upper  part  of  the  rectum  is  thrown 
into  folds  called  appendices  epiploic®.  There  are  three  semilunar  transverse 
folds,  one  in  the  upper  part  of  the  rectum  on  the  right  side,  another  about  the 
middle  on  the  left  side,  and  a  third  in  front,  opposite  the  base  of  the  bladder. 
They  are  called  the  folds  of  Houston. 

The  muscles  of  the  rectum  are  the  Sphincter  ani,  Internal  sphincter,  and 
Sphincter  tertius  of  Hyrtl.  The  rectum  is  supported  by  proper  duplications  of 
peritoneum,  the  meso-rectum,  and  other  fasciae. 

Liver. 

The  Liver  (Plate  CLIII)  is  the  largest  gland  in  the  body,  in  the  fetus  it  forms 
about  one-third  of  its  weight,  and  in  the  adult  about  one-thirty-sixth.  It  is 
situated  in  the  right  hypochondriac  and  epigastric  regions  and  may  extend  over 
into  the  left  hypochondriac  region.  It  has  three  surfaces,  viz.,  anterior,  pos- 
terior, and  inferior.  It  has  three  borders,  viz.,  superior,  inferior,  and  posterior; 
and  two  extremities.     It  is  entirely  covered  with  peritoneum. 

It  has  in  relation  with  it,  (Plate  CLII)  above,  the  Diaphragm  and  anterior 
abdominal  wall;  BELOw,the  cardiac  end  of  the  stomach,  hepatic  flexure  of  colon, 
right  kidney,  and  first  and  second  portions  of  the  duodenum; behind, the  tenth 
and  eleventh  thoracic  vertebra?,  crura  of  Diaphragm,lower  end  of  the  oesophagus, 
right  suprarental  capsule,  and  great  vessels. 

It  has  five  lobes,  (Plate  CLXII)  five  fissures,  five  vessels,  and  five  ligaments, 
Its  lobes  are  the  right,  left,  caudate,  quadrate,  and  Spigelian.  The  ligaments 
are  the  coronary,  the  right  and  left  lateral  or  triangular,  the  suspensory,  broad 
or  falciform,  and  the  round  ligament.  The  round  ligament  is  the  remains  of 
the  umbilical  vein;  all  the  other  ligaments  are  folds  of  peritoneum.  The  ves- 
sels are  the  hepatic  artery,  hepatic  veins,  the  bile  ducts,  lymphatic  vessels, 
and  the  portal  vein  which  breaks  up  into  capillaries  like  an  artery.  Its  fissures 
are  the  transverse,  fissure  for  the  gall-bladder,  fissure  for  the  inferior  vena  cava, 
ductus  venosus,  and  the  umbilical  fissure. 

The  liver  is  made  up  of  lobules  which  are  about  one-twelfth  of  an  inch  in 
diameter.  The  liver  has  various  functions — it  manufactures  bile  and  sugar 
and  has  other  metabolic  functions.  It  is  nourished  by  the  hepatic  artery  which 
carries  food  to  the  cells  and  by  the  portal  vein  which  carries  raw  material  to  be 
worked  over  by  the  cells. 

The  nerve  supply  to  the  liver  is  from  the  hepatic  plexus,  which  is  an  offset 
from  the  coeliac  plexus  and  receives  filaments  from  the  left  pneumogastric  and 
righl  phrenic. 

The  portal  veins  may  be  told  from  the  hepatic  as  the  portal  veins  remain 


ANATOMY    IN    A    NUTSHELL. 


325 


closed  because  they  are  surrounded  by  the  capsule  of  Glisson  while  the  hepatic 
veins  gape  open,  being  adherent  to  the  liver  substance. 

The  gall-bladder  retains  the  bile  and  is  situated  between  the  right   and 

PLATE  CXLVI. 


THYROID  CARTILAGE. 


CRICOID 


FIRST     THORACICT 


RIGHT  BRONCHUS 


LFFT  BRONCHUS 


CASuiAC  END 


TflflFTH  THORACIC  VERTEBRA 
CAELIAC  AXIS 


PYLORIC     END 
DUODENUM 


1IGHT  COMMON     ILIAC 


LEFT  COMMON  ILIAC 


The  (Esophagus  and  Stomach. 

quadrate  lobes  of  the  under  surface  of  the  liver,  it  is  of  pyriform  outline,  and 
when  full  is  seen  projecting  beyond  the  anterior  border  of  the  liver,  coming  to 
contact  with  the  abdominal  wall  opposite  the  ninth  costal  cartilage.  It  ex- 
tends as  far  back  as  the  transverse  fissure.  It  is  about  three  or  four  inches  long 
and  will  hold  about  one  and  one-half  ounces.  The  vessels  of  the  gall-bladder 
are  the  cystic  arterv  from  the  right  branch  of  hepatic  Two  cystic  veins  usually 
empty  into  the  right  branch  of  the  portal  vein,  twelve  or  fifteen  from  the  fundus 


326  ANATOMY    IN    A    NUTSHELL. 

go  directly  into  the  liver.  The  nerves  of  the  gall-bladder  are  from  the  coeliac 
plexus. 

The  hepatic  duct  is  formed  by  the  right  and  left  bile  ducts  descending  from 
the  liver.  The  biliary  ducts  are  the  cystic  ducts  which  come  from  the  neck  of 
the  gall-bladder.  It  joins  the  hepatic  forming  the  ductus  communis  chole- 
dochus.  These  three  are  called  the  biliary  ducts.  The  ductus  communis  chole- 
dochus  empties  into  the  descending  duodenum  about  three  inches  from  the 
pyloric  end  of  the  stomach. 

Pancreas  means  "all  flesh, "  (Plate  CXLVIII).  Insomeof  the  lower  animals 
it  is  known  as  the  sweetbread.  On  account  of  closely  resembling  the  parotid 
glands  it  is  called  the  abdominal  salivary  gland.  It  is  situated  in  front  of  the 
first  and  second  lumbar  vertebrse  and  behind  the  stomach.  It  has  a  head, a 
neck,  a  body  and  a  tail.  It  varies  considerably  in  size,  it  is  about  six  inches 
long,  from  half  an  inch  to  one  inch  in  thickness  and  weighs  about  three  ounces. 
The  pancreatic  duct,  also  called  the  duct  of  Wirsung,  extends  the  whole  length 
of  the  pancreas  and  opens  into  the  duodenum  about  three  inches  below  the 
pylorus  often  in  common  with  the  ductus  communis  choledochus.  The  head 
or  right  extremity  is  surrounded  by  the  curve  of  the  duodenum,  ductus  communis 
choledochus,  and  the  pancreatico-duodenalis  arteries.  The  tail  or  left  extremity 
lies  above  the  left  kidney  and  in  contact  with  the  lower  end  of  the  spleen. 


LESSON  XCIII. 

The  pancreas  receives  blood  from  the  splenic  artery  through  its  pancreatic 
branches,  and  from  the  superior  mesenteric  and  hepatic  by  the  inferior  and 
superior  pancreatico-duodenalis  arteries,  which  form  a  loop  running  round,  below, 
and  to  the  right  of  its  head.  The  blood  is  returned  into  the  portal  vein  by 
means  of  the  splenic  and  superior  mesenteric  veins.  The  lymphatics  terminate 
in  two  glands  which  lie  on  the  superior  mesenteric  veins.  The  nerve  supply  of 
the  pancreas  is  branches  of  the  solar  plexus  which  accompany  the  arteries  en- 
tering the  gland.  Sometimes  a  lobe  of  the  head  is  detached  and  has  a  duct  of 
its  own  opening  into  the  duodenum  about  an  inch  above  the  pancreatic  duct. 
This  In  be  is  called  the  lesser  pancreas. 

Tin-  portal  vein  (an  appendage  of  the  systemic  system)  is  a  single  large 
trunk  which  carries  venous  blood  from  viscera  to  the  liver;  there  it  splits  up 
into  capillaries,  which  then  unite  to  form  the  hepatic  veins,  which  empty  into 
the  inferior  vena  cava. 

The  portal  system  (Plate  CXXXVIII)  consists  of  four  large  veins  which 
drain  the  viscera  of  digestion  and  unite  to  form  the  portal  vein;  the  branches 
correspond  to  those  of  the  arteries,  are  always  single, and  have  no  valves.  The 
four  veins  are  the  splenic,  gastric,  and  superior  and  inferior  mesenteric. 

Si  perior  mesentkkic,  ascends  along  the  right  side  and  in  front  of  the 
artery,  passes  in  fronl  of  the  transverse  duodenum,  and  joins  with  the  splenic 
behind  the  upper  bolder  of  the  pancreas,  forming  the  portal  vein;  it  receives  the 
pancreatico-duodenalis  and  right  gastroepiploic  veins,  and  drains  the  csecum, 
ascending  and  transverse  colon,  and  small  intestine. 


ANATOMY    IX    A    NUTSHELL. 


327 


Splenic,  drains  the  spleen  by  several  branches,  which  soon  unite  into  one, 
this  runs  from  left  to  right,  below  the  artery,  in  a  groove  on  the  upper  and  back 
part  of  the  pancreas  and  unites  with  the  superior  mesenteric  at  the  greater  end 
of  the  pancreas  forming  the  portal  vein.  It  receives  the  vasa  brevia  (gastric,) 
pancreatic,  left  gastro-epiploic  and  inferior  mesenteric  veins. 

PLATE  CXLVIT. 


mm  t 

Showing  the  Viscera  Below  the  Diaphragm. 

Ineerior  mesenteric,  passes  upward  behind  the1  transverse  duodenum 
and  pancreas  to  end  in  the  splenic;  drains  the  rectum,  sigmoid  flexure,  and  de- 
scending colon;  and  lies  to  the  left  of  the  artery;  its  hemorrhoidal  branches 
inosculate  with  those  of  the  internal  iliac. 

Gastric,  two  in  number  as  follows:  The  pyloric,  corresponding  to  the 
pyloric  branch  of  the  hepatic  artery,  runs  on  the  lesser  curvature  towards  the 


328 


ANATOMY    IN    A   NUTSHELL. 


pylorus,  and  ends  in  the  portal  vein.  The  coronary,  corresponding  to  the  gas- 
tric artery,runs  on  the  lesser  curvature  toward  the  oesophagus,  and  then  curves 
downward  and  backward  in  the  lesser  omentum  to  end  in  the  portal  vein. 

Portal  vein  three  or  four  inches  long,  begins  behind  the  upper  border  of 
the  right  end  of  the  pancreas  by  the  union  of  the  splenic  and  superior  mesenteric. 
11   ascends  in  the  right  border  of  the  lesser  omentum,  between  and  behind  the 

PLATE  CXLVIII. 


SUPERIOR 

PANCREATICO  DUODENAUS 

INFERIOR 


ABDOMINAL    AORTA 

Showing  Blood  Supply  of  Stomach. 

hepatic  artery  (to  the  Left )  and  duct  (to  the  right,)  enters  the  transverse  fissure 
of  the  liver,and  becomes  a  dilated  (sinus);  it  then  divides  into  two  branches  (the 
right  is  larger  but  shorter)  which  enter  the  two  main  lobes  of  the  liver  and  split 
up.  It  receives  the  gastric  and  cystic  veins,  the  latter  from  the  gall-bladder. 
The  vessels  of  the  liver  form  two  sets:  The  superficial  vessels  arise,  over 
the  entire  surface,  in  the  subperitoneal  areolar  tissue.  Those  on  the  convex 
surface  form  four  groups,  viz..  (1)   three  or  four  branches  which  run  forward 


ANATOMY    IX    A    NUTSHELL. 


329 


and  then  upward  in  the  longitudinal  ligament,  and,  as  a  single  trunk,  through 
the  Diaphragm  to  the  anterior  mediastinal  glands  and  thence  to  the  right  lym- 
phatic duct:  (2)  branches  which  run  forward  and  around  the  anterior  margin  to 
the  under  surface,  and  thence  in  the  longitudinal  fissure  to  glands  in  the  lesser 
omentum;  (3)  branches  which  pass  outward  to  the  right  lateral  ligament  and 
thence,  coalescing,  either  through  the  Diaphragm  to  the  anterior  mediastinal 
glands,  or  inward,  across  the  crus.  to  the  thoracic  duct:  and  (4)   branches  which 

PLATE  CXLIX 

ABOVE 

DIAPHRAGM  LIVER  LESSER  OMENTUM 

M 


IN         FRONT 
C^HRAGM        LIVER     ABDOMINAL   WALL    K 


E      H     I      N     D 


e      LEFT     KIDNE1 
=>/ CAPSULE 
aV-PANCREAS 
l.  \plEEN 


w  c      GREAT  VESSELS 

-»  a/ SOLAR     PLEXUS 

t  oVTRANSVERSE     MESO    COLON 

Z  «*-      CRURA    OF     DIAPHRAGM 


BELOW 

'eat  omentum      transverse  colon        3astr0-  splenic   omeutum 
Showing  the  Muscular  Coats  and  Relations  of  the  Stomach. 


run  outward  from  the  left  lobe  to  the  left  lateral  ligament,  and  thence  through 
the  Diaphragm  to  the  anterior  mediastinal  glands. 

Those  on  the  under  surface  form  three  groups,  viz.,  (1)  branches  arising 
to  the  right  of  the  gall-bladder  and  passing  to  the  lumbar  glands;  (2)  branches 
Burroduning  the  gall-bladder  in  a  plexus  and  passing,  with  the  hepatic  Vessels 
to  glands  in  the  lesser  omentum  :  and  (3)  branches  arising  to  the  left  of  the  gall- 
bladder and  passing  to  the  oesophageal  glands  or  glands  along  the  lesser  curva- 
ture of  the  stomach. 

The  deep  vessels  of  the  liver  accompany  the  branches  of  the  portal  vein 
and  hepatic  duct  and  artery:  they  escape  a1  the  transverse  fissure  and  either 
enter  glands  placed  along  the  lesser  curvature  or  the  stomach  and  behind  the 
pancreas,  or  join  a  lacteal  before  it  enters  the  thoracic  duct. 


330 


ANATOMY    IX    A    NUTSHELL. 


LESSON  XCIV. 

Spinal  Cord.     (Plates     1V-V-CXCII-CXCIII-CXCIV). 

The  spinal  cord  belongs  to  the  cerebrospinal  or  central  nervous  sys- 
tem, which  ('(insists  of  the  brain  and  spinal  cord.  The  twelve  pairs  of  cranial 
nerves,  and  thirty-one  pairs  of  spinal  nerves  make  the  peripheral  system. 
Besides  these  two  systems  there  is  the  sympathetic  system  which  is  connected 
with  these  two  and  closely  associated  with  the  vessels,  viscera,  and  glands. 

The  spinal  cord  extends  from  the  level  of  the  foramen  magnum  (below  the 
decussation  of  the  pyramids  of  the  medulla)  to  the  level  of  the  upper  border  of 
the  second  lumbar  vertebra,  sometimes  only  to  the  first  lumbar  vertebrae.  Its 
length  is  from  fifteen  to  eighteen  inches  and  its  average  weight  about  one  and 
one-half  ounces.  It  is  a  somewhat  flattened  cylinder,  wider  in  the  transverse 
diameter.  It  follows  the  curves  of  the  spinal  column  in  which  it  is  lodged.  It 
is  composed  of  white  and  gray  matter,  the  white  on  the  exterior,  and  the  gray 
on  the  interior.  The  gray  matter  of  the  cord  consists  of  two  kinds.  (1)  SUB- 
STANTIA   GELATINOSA     (RoLAXDI    and    CENTRALIS)     and     (2)    SUBSTANTIA     SPON- 

GIOSA.     Rolandi  forms  A   cap  to   the  posterior  horn.     It  extends  the  whole 
length  of  the  cord  into  the  medulla  where  it  becomes  enlarged  and  has  large 

PLATE  CL. 


SMALL     INTESTINE 


Ot'SCENDISG     COLON 


ASCENDING   COLON 


AORTA 


NFERIOR  VENA  CAVA 


THEMESSENTERY 


Showing  the  Peritoneum  as  a  Closed  Sac. 

nerve  cells  and  forms  one  of  the  end  stations  for  the  sensory  divisions  of  the 
fifth  nerve.  The  substantia  gelatinosa  Rolandi  was  formerly  thought  to  be 
rich  in  neruoglia  tissue,  but  in  fad  it  is  vert  poor  in  this  tissue.  The  cord 
has  two  enlargements,  i  he  <  i:i;\  ecal  ami  the  lumbar.  The  former  is  between 
the  third  cervical  and  the  second  thoracic  vertebra,  reaching  its  greatest  diameter, 
which  is  transverse,  in  the  sixth  cervical,  The  latter  is  between  the  ninth  thor- 
acic and  6rs1  lumbar;  its  greatesl  diameter,  which  is  antero-posterior,  is  opposite 
the  twelfth  thoracic  vertebra.  These  enlargements  occur  where  the  nerves  are 
given  off  to  supply  the  extremities.  A-  the  cord  is  shorter  than  the  canal,  the 
lumbar,  sacral,  and  coccygeal  nerve  roots  have  a  longer  course  than  the  nerve 


ANATOMY    IN    A    NUTSHELL. 


331 


roots  above  them.     The  last  nerve  roots  have  the  appearance  of  a  horse's 
tail  (cam la  equina). 

The  neuroglia  consists  of  a  homogenous  transparent  matrix  of  a  network 
of  very  (1)  delicate  fibrillar  and  of  (2)  small  stellate  or  branched  cells,  the 
neuroglia  cells.     Formerly  it   was  considered  connective  tissue   but  neuroglia 

PLATE  CLI. 


LESSER      OMENTUM 


PARIETAL   PERITONEUM 
/ISCERAL     PERITONEUM 


GREAT  OMENTUM 


GREAT     CAVITY  OF  PERITONEUM 


FORAMEN  OF  WINSLOW 
SPINAL     COLUMN 


KANCREAS 


OUOCENUM 

TRANSVERSE    MESOCOLON 
TRANSVERSE     COLON 


THE  MESSENTERY 


POUCH         OF 
0    0  (I    (i  L   A  S 


A  Sagittal  Section  of  the  Trunk  Showing  the  Peritoneum. 


is  developed  from  the  epiblast  and  connective  tissue  from  mesoblast.  In  addi- 
tion to  forming  a  ground  substance  in  which  the  nerve  fibers,  nerve  cells, 
and  blood  vessels  are  imbedded,  a  considerable  accumulation  of  neuroglia  takes 
place  in  these  situations;  (1)  ox  the  OUTER  SURFACE  OF  the  CORD,  beneath  the 
pia  mater,  (2)  around  the  central  canal,  and  (3)  i\  the  anterior  born. 
The  conus  inedullaris  is  the  coin-like  termination  of  the  cord,  and  this 


332 


ANATOMY    IN    A    NUTSHELL. 


terminates  in  a  .slender  thread,  the  filum  terminale.  The  filum  terminate  is 
a  continuation  of  the  pia  mater  as  far  as  the  base  of  the  coccyx,  to  the  periosteum 
of  which  it  is  attached.  It  contains  very  litttle  nervous  matter,  and  is  distin- 
guished from  the  nerves  of  the  cauda  equina  by  its  glistening  white  appearance. 
The  membranes  of  the  cord  are  the  same  as  those  of  the  brain,  viz.,  dura 
mater,  arachnoid,  and  pia  mater.  The  dura  mater  of  the  cord  differs  from  that 
of  the  brain,  in  that  it  does  not  form  (1)  the  internal  periosteum,  does  not 
adhere  (2)  to  the  walls,  does  not  contain  (3)  sinuses,  and  does  not  send  (4) 
infoldings  into  the  fissures  of  the  cord.  The  nerve  supply  of  the  dura 
mater  is  from  the  spinal  nerves  and  filaments  from  the  sympathetic.  The  dura 
mater  of  both  brain  and  cord  send  tubular  prolongations  over  the  nerves. 

PLATE    CLII. 


DIAPHRAGM      AND       ANTERIOR     WALL  OF      ABDOMEN 


behind 


TENTH  AND  ELEVENTH 
THORACIC  VERTEBRAE 


RIGHT 

SUPRARENAL 

CAPSULE 


GREAT    VESSELS 


CARDIAC  END  OF    STOMACH         HEPATIC   FLEXURE  OF    COLON        RIP^-    KIDNEY 
FIRST      AND     SECOND       PORTIONS       OF     DUODENUM 

The  Relations  of  the  Liver. 


It  is  separated  from  the  walls  of  the  spinal  canal  by  fat,  loose  areolar  tissue,  and 
anterior  and  posterior  plexuses  of  veins.  It  is  attached  above  to  the  foramen 
magnum,  to  the  axis  and  the  third  cervical  vertebra,  and  below  to  the 
posterior  surface  of  BASE  of  the  cocgyx.  The  subdural  space  is  between  the 
dura  mater  and  the  arachnoid  and  contains  a  small  quantity  of  cerebro-spinal 
fluid.  The  inner  surface  of  the  dura  mater  is  lined  with  endothelium,  and  is 
abundantly  supplied  with  nerves  and  blood  vessels. 

The  arachnoid  of  the  cord  is  more  delicate  than  that  of  the  brain,  but  re- 
sembles it  in  sending  tubular  prolongations  over  the  nerves.  It  is  devoid  of 
nerves  and  has  bu1  a  slight  blood  supply.  It  extends  as  far  as  the  second  or 
third  sacral  vertebra.  It  forms  a  long  sac  and  the  space  between  it  and  the 
pia  mater  is  called  the  subarachnoid  space.  This  space  contains  cerebro-spinal 
fluid,  which  is  about  one  ounce  in  this  space  and  two  ounces  in  the  ventricles. 


ANATOMY    IN  A    NUTSHELL. 


333 


The  pia  mater  is  the  inner  membrane  of  the  cord.  It  is  closely  adherent 
to  the  cord  and  sends  septa  into  the  anterior  and  posterior  fissures  of  the  cord. 
The  linea  splendens  is  the  thickened  line  of  pia  mater  along  the  anterior  median 
line.  The  ligamenta  denticulata  are  fibrous  bands  which  are  attached  to  the 
median  lateral  aspect  of  the  pia  mater  from  the  level  of  the  foramen  magnum  to 
the  level  of  the  first  lumbar  vertebra.  The  ligaments  are  midway  between  the 
anterior  and  posterior  nerve  roots.  There  are  about  twenty-one  ligaments  on 
each  side,  extending  from  the  pia  mater  to  the  dura  mater,  carrying  the  arach- 
noid along  which  it,  not  piercing  it.  The  highest  one  of  the  processes  is  placed 
between  the  hypoglossal  nerve  and  the  vertebral  artery. 

PLATE  CLIII. 


LEFT 

LATERAL     LIGAMENT 


SITE  OF  THE  SPIGELIAN  LOBE 

INFERIOR  VENA  CAVA 

The  Superior  Surface  of  the  Liver. 

The  reticula  is  a  network  of  gray  matter,  enclosing  white  fibers  in  its  meshes. 
It  is  situated  at  the  base  of  the  posterior  horn  externally,  directly  opposite  the 
columns  of  Clarke.  The  columns  of  Clarke  are  two  symmetrically  placed  tracts 
of  medium  sized  nerve  cells  of  thespinal  cord,  latero-dorsal of  the  central  canal, 
confined  chiefly  to  the  dorsal  region,  but  also  extending  a  little  above  and  below  it. 

LESSON  XCV.     ' 

The  anterior  and  posterior  nerve  roots  of  the  spinal  cord  emerge  from  the 
antero-lateral  and  postore -lateral  aspects  of  the  cord  respectively,  and  form  a 
double  row  on  each  side  of  it.  The  anterior  roots  arise  from  the  anterior  horn 
of  the  gray  matter  and  contain  motor  fibers;  the  posterior  roots  arise  from  the 
posterior  horn  and  contain  sensory  fibers. 

The  central  canal  is  in  the  centre  of  the  gray  commissure,  and  is  lined  with 


334 


ANATOMY    IN    A    NUTSHELL. 


columnar  ciliated  epithelium  in  the  fetus,  but  in  the  adult  the  cilia  have  dis- 
appeared and  fill  the  canal  with  their  remains.  It  is  continuous  above  with  the 
fourth  ventricle  of  the  brain.  This  canal  is  the  remains  of  the  original  neural 
canal  of  the  embryo,  from  the  walls  of  which  the  spinal  cord  is  formed.  The 
sinus  rhomboidalis  inferior  or  ventricularis  terminalis  is  a  dilatation  of  the  cen- 
tral canal  in  the  conus  medullaris. 

Diseases  of  the  spinal  cord  may  affect  its  entire  transverse  area,  or  certain 
portions  of  it  in  varying  lengths,  or  it  may  begin  at  any  level  and  extend  up- 
ward or  downward,  in  which  case,  being  designated  as  ascending  or  descending. 

PLATE  CL1V. 


RIGHT  LOBE' 


BILE  DUCT 

The  Inferior  Surface  of  the  Liver. 

A  tumor  would  be  an  example  of  a  focal  disease,  or  disease  of  one  of  the  seg- 
ments (a  portion  of  the  cord  with  a  pair  of  nerves).  Locomotor  ataxia  is  an 
example  of  a  systemic  disease. 

Fractures  of  the  spinal  column  above  the  fifth  cervical  vertebra — above  the 
origirj  of  the  phrenic  nerve,  are  almost  always  fatal  because  of  paralysis  of  the 
diaphragm.  Fractures  of  the  fifth,  sixth,  and  seventh  vertebrae  cause  paraly- 
sis of  the  intercostal  and  abdominal  muscles  and  death  usually  results. 
In  fractures  of  the  Lower  part  of  the  thoracic  region  the  prognosis  is  not 
so  unfavorable.  Degenerations  in  motor  tracts  of  the  cord  descend,  and 
the  sensory  tracts  ascend.  This  is  due  to  the  fact  that  the  trophic  centers  of 
the  m«>ti»r  tracts  are  in  the  okay  matter  of  the  brain,  while  those  of  the  sen- 
sory  iraci-  arc  in  the  G  \m.li  \  upon  the  posterior  roots  of  the  spinal  nerves. 
In  the  crossed  pyramidal  tracts  we  find  three  sets  of  fibers,  motor,  vasomotor, 


ANATOMY   IN    A    NUTSHELL.  335 

and  fibers  which  carry  impulses  for  inhibition  of  reflex  action.  The  vasomotor 
and  inhibitory  fibers  pass  to  the  motor  cells  of  the  anterior  horn.  When  the 
crossed  pyramidal  tract  degenerates  these  inhibitory  and  vasomotor  fibers  are 
included,  and  dilatation  of  the  blood  vessels  and  increased  reflexes  result. 

In  spina  bifida  there  is  an  overbundance  of  cerebro-spinal  fluid  with  faulty 
development  of  the  posterior  walls  of  the  lumbar  portion  of  the  spinal  canal. 
In  this  condition  the  membranes  are  pushed  through  the  opening  in  the  spinal 
canal  by  the  weight  of  the  cerebro-spinal  fluid. 

The  subarachnoid  spaces  of  the  cord  and  brain  are  continuous  and  connected 

PLATE  CLY. 

3.     PLEXIUS  OF  CAPILLARY    BLOOD-VESSELS  WITHIN  THE  LOBULE. 


1.     INTERLOBULAR  VEINS  .  «      R  1 V.  2.      INTRALOBULAR  VEIN. 


4.  TWIGS     OF     INTERLOBULAR  VEIN,  PASSING  TO     THE    ADJACENT    LOBULES. 

The  Vessels  of  a  Lobule  of  the  Liver. 

with  the  fourth  ventricle  by  the  foramina  of  Magendie,  Key,  and  Retzius. 
The  opening  of  a  spina  bifida  may  drain  the  cerebro-spinal  fluid  from  the  brain 
and  result  in  fatal  convulsions. 

The  fissures  of  the  cord  are  antero-median.  postero-median,  two  antero- 
lateral, two  postero-lateral.  and  two  dorso-intermediate  fissures.  These  fissures 
divide  the  cord  into  eight  columns,  viz..  ventral,  lateral,  "Goll,  ami  Burdack 
(posterior.)"     These  are  on  each  side. 

The  ascending  and  descending  fibers  of  the  white  matter  of  the  cord 
arranged  in  tracts,  but  these  tract-  are  not  recognizable  in  the  adult  cord,  but 
only  during  development  or  when  affected  with  disease  or  degeneration.  The 
facts  concerning  the  tracts  have  been  ascertained  by  embryologies!  and  path- 
ological research.  This  division  of  fissures  is  somewhat  arbitrary,  a-  the  place 
where  the  anterior  nerve  roots  leave  the  cord  i>  not  always  called  a  fissure,  and 
the  dorso-intermediate  one  is  only  in  the  cervical  region.  If  we  lake  this  di- 
vision there  are  only  eight  fissures  and  eighl  columns  in  the  spinal  cord.  The 
antero-median  fissure  extends  about  one-third  the  diameter  of  the  cord,  toward 


336 


ANATOMY    IN   A    NUTSHELL. 


the  anterior  white  commissure.  It  has  in  it  a  pro  cess  of  pia  mater  which  conducts 
blood  to  the  cord.  Although  there  are  only  eight  columns  in  the  whole  cord, 
there  are  ten  tracts  in  the  white  matter  of  each  lateral  half  of  the  cord.  As  a 
rule  the  tracts  are  much  smaller  than  the  columns,  but  sometimes  they  are 
equal,  as  in  Goll  and  Burdack.     Tracts  one,  two,  three,  four,  and  five  are  ascend- 

PLATE  CLVI. 


Showing  the  Blood  Supply  to  the  Small  Intestine. 

ing  tracts;  eight,  nine,  and  ten  are  descending  tracts,  and  six  and  seven  are 
association  tracts.  (Plate  IV).  The  gray  matter  in  the  cord  is  in  the  form  of 
a  capital  letter  "H;"  the  horizontal  portion  is  called  the  gray  commissure,  and 
the  portion  in  front  of  the  central  canal  is  the  anterior  gray  commissure,  and 
the  portion  behind  it  the  posterior  gray  commissure.  The  portion  of  white 
matter  in  front  of  the  gray  commissure  is  the  white  commissure.  The  blood 
supply  of  the  spinal  cord  and  its  membranes  is  (1)  from  the  lateral  spinal,  which 
are  branches  from  the  subclavian,  from  thoracic  intercostals  of  the  aorta,  from 


ANATOMY    IN    A    NUTSHELL. 


337 


the  lumbar,  and  from  the  internal  iliac  arteries.  (2)  From  the  anterior  and 
posterior  spinal  branches  of  the  vertebral  arteries.  The  anterior  spinal  arter- 
ies are  two  in  number;  and  come  from  the  vertebrate,  just  before  they  unite 
to  make  the  basilar  at  the  foramen  magnum,  the  anterior  spinals  unite  to  make  one 
artery,  the  anterior  median  artery.   This  artery  lies  in  the  pia  mater,  which  it 

PLATE  CLVII. 


LEFT  COMMON 
ILIAC  VEIN 


MIDDLE    SACRAL  ARTERY  AND  VEIN 


Showing  the  Blood  Supply  to  the  Large  [ntestine. 


supplies,  and  extends  the  wholelength  of  the  cord.  It  recieves  branches  from  the 
lateral  spinal  arteries,  and  it  sends  branches  into  thesubstance  oi  the  spinal  cord. 
The  posterior  spinals  are  also  two  in  number;  they  come  from  the  vertebral  arteries 

a,  the  side  of  the  medulla  (occasionally  from  the  posterior  inferior  cerebellar); 
they  pass  down  behind  the  posterior  nerve  roots  (occasionally  there  is  another 
branch  in  front  of  the  posterior  nerve  roots)  to  the  cauda  equina.      Each  Beg- 


PLATE  CLVIH. 


NO.  2. 


NO.  3. 


Showing  the  Vermiform  Appendix  and  Four  Forms  of  the  Cecum, 

338 


ANATOMY    IN    A    NUTSHELL. 


339 


nient  (  a  part  of  the  cord  with  a  pair  or  nerves  )  has  a  blood  supply  which  is 
made  by  the  anterior  and  posterior  spinal,  reinforced  by  the  lateral  spinal, 
making  a  ring  around  the  segment.  Branches  are  given  from  each  segment 
to  the  segment  above  and  below.  The  blood  supply  of  the  vertebral  column  and 
its  ariculation  is  the  vertebral,  occipital,  ascending  pharyngeal,  ascending 
cervical,  intercostal,  lumbar,  ilio-lumbar,  sacra  media,  and  lateral  sacral.  The 
nerve  supply  is  from  the  spinal  nerves. 


LESSON  XCVI. 

Brain.     (Plates    CLXVIII  -CLXXXIII.) 

There  is  but  one  nervous  system,  consisting  of  three  great  divisions.      The 

brain  and  spinal  cord  make  the  central  system,  the   twelve  pairs  of  cranial 

and  the  thirty-one  pairs  of  spinal  nerves  make  the  peripheral  system,  and  the 

third  division  is  called  the  sympathktic  system.     This  last  svsteni  is   called 


PLATE  CLIX. 


ASCENDING   COLON 


CAECUM.  '     ^§^-=^^5^  4PPFN0IX 

The  Ileo-Ctecal  Valve. 


the  nerve  of  organic  life  while  the  central  one  is  called  the  nervous  system  of 
animal  life.  The  specific  gravity  of  the  nervous  system  is  L.036,  the  brain 
1.038  and  the  spinal  cord  1.034.  The  reaction  is  alkaline,  which  is  Lessened  by 
activity,  owing  to  lactic  acid  being  developed.  The  white  matter  is  more 
alkaline  than  the  gray.  The  brain  is  a  collection  of  gray  ganglia  connected  by 
white  commissures. 

The  following  are  the  principal  transverse  commissures! 

1.  Anterior  commissure. 

2.  Middle  commissure. 

3.  Posterior  commissure; 

4.  Corpus  callosum. 

5.  Optic  commissure. 

6.  Pons  Varolii. 


340 


ANATOMY    IN    A  NUTSHELL. 


7.  Fornix,  which  is  a  longitudinal  commissure  also. 

8.  Posterior  or  inferior  medullary  velum. 

9.  Valve  of  Vieussens,  anterior  or  superior  medullary  velum. 
The  following  are  the  principal  longitudinal  commissures: 

1.  Olfactory  tracts. 

2.  Taenia  semicircularis. 

3.  Crura  cerebri. 

4.  Processus-e-cerebello  ad  testes. 

5.  Peduncles  of  the  pineal  gland. 

6.  Fornix. 

7.  Infundibuluni. 

8.  Lamina  Cinerea. 
0.  Gyrus  fornicatus. 

10.  Fasciculus  unciformis. 


LESSON  XCVII. 

The  extensor  of  the  brain,  Avhich  is  called  cortex,  is  gray,  while  the  interior 
is  white.  The  average  weight  of  the  brain  is  forty-nine  and  one-half-ounces. 
in  the  male,  while  it  is  a  little  lighter  in  the  female. 

PLATE  CLX. 


MUSCULAR  BANDS  —  TAENIAfc      COLI 

Transverse  Skction  of  the  Large  Ixtkstine. 

The  nervous  system  is  developed  from  the  neural  tube.  (Plates  CLXIV- 
CLXV-CLXVI-CLXV1 ! ).  The  substance  of  the  brain  and  cord  are  made  from 
a  thickening  of  the  walls  of  the  tube;  the  hollow  of  the  tube  makes  the  central 
canal  of  the  cord  and  the  ventricles  of  the  brain.  The  rooms,  or  ventricles  in 
the  brain  are  filled  with  cerebro-S]  Lnal  fluid  which  acts  as  a  cushion  for  the 
brain  and  cord.  There  are  five  ventricles  in  the  brain.  The  central  canal  in 
the  cord  is  dilated  as  it  passes  into  the  brain,  between  the  cerebellum  behind, 
and  the  pons   wi)  medulla  i x  front;  this  dilatation  is  called  the  fourth  ven- 


ANATOMY    IN    A    NUTSHELL 


341 


tricle;  as  this  passage  goes  forward  between  the  crura  cerebri  in  front,  and 
the  corpora  quadrigemina  behind,  it  is  contracted  and  is  called  the  aque- 
duct of  Sylvius  (iter  e  tertio  ad  quartum  ventriculum) ;  from  here  it  passes  into 
a  narrow  but  high  room,  called  the  third  ventricle,  which  is  between  the  optic 
thalami;  these  two  ventricles  are  in  the  median  line  of  the  brain.  There  are 
two  lateral  ventricles,  one  in  each  hemisphere,  which  are  connected  with 
the  third  one  by  the  foramen  of  Monro.  There  is  the  fifth  ventricle  not  con- 
nected with  the  others;  it  is  situated  in  the  septum  lucidum. 

The  brain  consists  of  four  main  parts,  (1)  fore-brain,  (2)  inter-brain,  (3) 
mid-brain,  and  (4)  hind-brain.     The  brain  is  called  encephalon;  the  cerebral 

PLATE  CLXI. 


CYSTIC     DUCT 

SUPRARENAL 
CAPSULE 


SPLENIC  ARTERY 


ORIFICE     OF  ACCESSORY     PANCREATIC     DUCT. 

ORIFICE  OF  BILE  AND  PANCREATIC   DUCTS 


SUP.    MESENTERIC  ARTERY 


interior  vena  cava. 
Pancreas,  Duodenum  and  Kidney. 

hemispheres  are  called  prosencephalon;  the  parts  around  the  third  ventricle 
are  called  the  thalamencephalon ;  the  parts  around  the  aqueduct  of  Sylvius  arc 
called  the  mesencephalon;  the  pons  and  cerebellum,  are  called  the  epencephalon; 

the  medulla  is  called  the  metencephalon ;  the  olfactory  tract  is  called  the  rhin- 
encephalon.  The  spinal  cord  is  called  the  myelon.  The  encephalon  and  the 
myelon  constitute  the  neuron.  The  brain,  like  the  spinal  cord,  has  three  coats. 
viz.,  dura  mater,  arachnoid,  and  pia  mater.  The  arteries  which  supply  the 
dura  mater  are  derived  chiefly  from  the  anterior,  middle,  and  posterior  menin- 
geal. The  nerve  supply  of  the  dura  mater  is  the  sympathetic,*  rasserian  ganglion, 
fourth,  fifth,  tenth,  and  twelfth.  The  arachnoid  has  but  a  limited  blood  sup- 
ply, and  the  nerve  supply  is  from  the  motor  division  of  the  fifth,  the  seventh, 
and  the  spinal  accessory.     The  pia  mater  receives  blood  supply  from  the  ni- 


342 


ANATOMY    IX    A    NUTSHELL. 


ternal  carotid  and  vertebral  arteries.     The  nerve  supply  is  from  the  sympathetic, 
the  third,  fifth,  sixth,  seventh,  ninth,  tenth,  and  eleventh  cranial  nerves. 

The  exterior  of  the  cerebrum  is  uneven,  having  hills  and  valleys.  The  hills 
are  called  gyri,  or  convolutions;  the  valleys  are  called  sulci,  or  Assures.  The 
larger  fissures  are  called  primary,  the  others  secondary.  The  primary  are 
either  complete  or  incomplete.  A  complete  Assure  makes  an  impression  in  a 
ventricle  of  the  brain.  They  are  all  on  the  mesial  surface  of  the  brain.  They 
are  (1)  the  dentate,  which  makes  the  hippocampus  major  in  the  descending 
lioiii  ;  (2)  the  ealcarine,  which  makes  the  hippocampus  minor  in  the  posterior 


PLATECLXII. 


UUCTUS  VENOSUS  FISSURE 
LEFT  LOBE 


RIGHT  LOBE 
VENA  CAVA    FISSURE 


UMB,LICAL    FISSURE  -GALLBLADDER    F.-SSl). 

Lobes  and  Fissuses  of  the  Liver. 

horn;  and  (3)  the  collateral,  which  makes  the  eminentia  collaterals  in  the  de- 
scending horn.  There  are  two  others  which  are  sometimes  called  complete 
fissures,  the  transverse,  which  has  opposite  it  the  choroid  plexus,  and  the 
fissure  of  Sylvius,  which  has  opposite  it  the  corpora  striata.  The  last  two 
are  not  on  the  mesial  surface. 


LESSON  XCVIII. 

The  right  and  left  lobes  of  the  cerebrum  are  connected  by  the  corpus 
CALLOSUM.     There  are  five  lobes  in  each  hemisphere  of  the  brain. 

The  brain  is  the  encephalon;  the  part  of  the  cerebro-spinal  axis  which  is 
contained  in  the  cranium.  Its  divisions  are  the  cerebrum  or  brain  proper,  the 
cerebellum  or  little  brain,  the  pons  Varolii,  and  the  medulla  oblongata.  The 
average  weighl  of  the  brain  in  the  male  is  forty-nine  and  one-half  ounces,  in 
the  female  forty-four  ounces.  Cuvier's  brain  weighed  more  than  sixty-four 
ounces.  The  human  brain  weighs  more  than  that  of  any  other  animal,  except 
the  elephant  and  whale.  The  elephant's  brain  weighs  about  ten  pounds;  that 
of  the  whale  five  pounds. 

Like  the  bark  (cortex)  of  a  tree  the  cortical  layer  of  the  brain  covers  the 
surfaces  of  the  brain.      It  is  composed  of  cellular  nerve-material. 


ANATOMY    IN   A    NUTSHELL. 


343 


The  Assures  or  sulci  of  the  brain  are  infoldings  of  the  cortex  and  the  more 
numerous  and  deeper  they  are,  the  greater  is  the  amount  of  the  peripheral  gray 
substance. 

The  gray  matter  of  the  brain  which  invests  the  cerebellum  and  cerebrum, 
is  also  called  the  cortical  substance,  in  distinction  from  the  white  or  medullary 
substance  of  the  interior.  There  are  several  ganglia  or  collections  of  gray  mat- 
ter in  the  interior,  as  the  corpora  striata,  the  optic  thalami,  the  optic 
lobes  or  corpora  quadrigemina,the  corpora  dentata  of  the  cerebellum,  and 
the  corpora  olivaria  of  the  medulla  oblongata.  There  are  two  non-nerv- 
ous structures  connected  with  the  brain,  the  conarium  or  epiphpsis  cerebri 
and  the  pituitary  body  or  hypophysis  cerebri. 

The  principal  fissures  of  the  cerebrum  are:     (Plates  CLXXV-CLXIX), 

(a)  The  longitudinal  fissure  which  separates  the  two  hemispheres. 

PLATE  CLXIII. 


DUODENUM 


SEROUS  COAT 

LONGITUDINAL  MUSCULAR  LAYER 

CIRCULAR  MUSCULAR    LAYER 

AREOLAR    COAT 

MUCOUS       COAT 


The  Four  Coats  of  the  Stomach  and  the  Pyloric  Orifice. 

(b)  The  Sylvian  fissure  is  the  largest,  deepest,  and  most  constant  of  the 
fissures  of  the  brain.  It  has  a  short  anterior  and  long  posterior  branch,  the 
latter  separating  the  temporal  from  the  parietal  lobes.  It  has  the  middle  cere- 
bral artery  in  it,  lesser  wing  of  sphenoid  and  central  lobe  or  isle  of  Reil. 

(c)  The  fissure  of  Rolando  or  central  fissure  is  a  deep  sulcus  separating 
the  frontal  and  parietal  lobes  of  the  cerebrum  on  each  side. 

(d)  Parieto-occipital  fissure  extends  from  the  longitudinal  fissure  outwards 
for  about,  one  inch  between  the  parietal  and  occipital  lobes. 

(e)  The  transverse  fissure  is  a  crevice  through  which  the  invagination  of 
the  pia  mater  is  effected,  it  starts  from  the  porta  (foramen  of  Monro)  nearly 
to  the  distal  end  of  the  middle  horn  on  each  side.  It  is  at  the  base  of  the  brain. 
It  is  also  called  choroid  fissure. 

(f)  Calloso -marginal  fissure  is  nearly  concentric  with  the  callosal  and  also 
with  that  of  the  margin  of  the  hemisphere  until  a  point  above  the  hind  end  of 
the  callosum  is  reached,  at  which  the  fissure  turns  and  runs  upward  and  back- 
ward to  the  upper  border. 


344 


ANATOMY    IN    A   NUTSHELL. 


(g)  Calcarine  fissure  (from  calcar,  "a  spur"),  runs  from  near  the  rather 
pointed  hind  end  of  the  hemisphere  upward  and  forward,  and  just  beyond  the 
middle  at  the  point  where  it  receives  the  parieto-occipital,  binds  downward 
and  terminates  beneath  the  rear  end  of  the  callosum.  Encircling  the  callosum 
is  a  fissure,  called  the  callosal. 

(h)  First  tempro-sphenc tidal  fissure  is  below  the  fissure  of  Sylvius  on  the 
lateral  surface  of  the  brain. 


LESSON  XCIX 

TllK   PRINCIPAL  LOBES  OF  THE  CEREBRUM   ARE:       (Plates  CLXXV). 

1.  Frontal  lobe  is  the  anterior  one  of  the  cerebrum,  separated  from  the 
parietal  by  the  fissure  of  Rolando  or  central  fissure. 

2.  Parietal  lobe  is  the  middle  one  of  the  vault  of  the  cerebrum,  separated 


PLATE  CLXIV 


GERMINAL    AREA 


NEURAL  GROOVE 


PRIMITIVE     STREAK 


FORE-  BRAIN      (RUDIMENT  OF  CEREBRAL  HEMISPrtEKtS 
OPTIC       VESICLE 

FIRST  CEREBRAL  VESICLE 
SECOND  CEREBRAL     VESICLE 
THIRD  CEREBRAL  VESICLE 


MESODERM 


NEURAL    CREST 


Showing  Germinal  Area. 

from  the  frontal  by  the  central  fissure. or  fissureof  Rolando  and  marked  off  from 
the  occipital  by  the  parito-occipital  fissure.  It  is  divided  by  an  intra-parietal 
fissure  int"  a  superior  and  inferior  parietal  lobe. 

'■'<.  Occipital  lobe  is  the  posterior  portion  of  the  cerebrum  marked  off  from 
tin    parietal  lobe  by  the  parieto-< iccipital  fissure. 

4.  Temporo-sphenoidal  lobe,  also  called  temporal,  is  the  lobe  of  cerebrum 
which  occupies  the  middle  cerebral  fossa  of  the  skull,  it  is  separated  from  the 
frontal  and  parietal  lobes  by  the  fissure  of  Sylvius. 

.">.  The  Central  lobe  or  island  of  lb  il  is  also  called  the  lobule  of  the  Sylvian 
fissure,  lobule  of  the  corpus  striatum    is  a  portion  of  the  cerebral  cortex  con- 


ANATOMY    IN   A   NUTSHELL. 


345 


cealed  in  the  Sylvian  fissure,  consisting  of  five  or  six  radiations,  convolutions, 
or  the  gyri  operti  ("covered  gyrus"). 

Different  human  brains  vary  in  details  of  the  gyri.  and  the  same  brain  may 
differ  on  its  opposite  sides.  The  gyri  are  best  marked  when  one  reaches  his 
highest  mental  development. 

The  principal  gyri  or  convolutions  are:  (Plate  CLXXV-CLXXXIII- 
CLXXXIV). 

1.  Angular  gyrus  is  a  short  one,  arching  over  the  upper  extremity  of  the 
superior  temporal  fissure,  the  hindmost  one  of  the  four  parietal  gyri,  separated 
by  a  short  vertical  sulcus  from  the  supra-marginal  gyrus. 

2.  Annectent  gyrus  is  a  small  fold  wich  may  connect  large  or  primary  con- 
volutions; applied  to  several  such  gyri  on  the  occipital  lobe,  as  those  forming 
the  connections  of  the  cuneus  or  occipital  lobule. 

3  Ascending  frontal  gyrus  is  the  one  bounding  the  fissure  of  Rolando  in 
front. 


PLATE  CLXV. 

SURFACE  ECTODERM    ^^ 
NEURAL  CREST  (DISAPPEARING) 


TJEURAL     CREST 
GANGLION 


POSTERIOR    NERve 


SPINAL    GANGLION 

SYMPATHETIC     GANGLION  /  ANTERIOR  NERVE  ROOT 

Showing  the  Development  of  the  Sympathetic  Nerve. 

As  ascending  parietal  is  the  one  bounding  the  fissure  of  Rolando  behind. 

5.  Calossal  gyrus  is  a  convolution  of  the  median  surface  of  the  cerebrum 
immedately  over  the  corpus  callosum  and  below  the  calloso-marginal  fissure. 
It  is  continuous  behind  with  the  gyrus  hippocampi,  and  ends  in  the  gyrus  un- 
cinatus,  also  called  gyrus  fornicatus,  convolution  of  the  corpus  callosum. 

6.  Cuneate  gyrus  is  one  of  the  occipital  lobe  appealing  as  a  wedge-shaped 
figure  on  the  median  aspect  of  the  cerebrum  in  the  fork  between  the  parieto- 
occipital sulcus  and  the  calcarine  sulcus,  also  called  occipital  lobule  and  cuneus. 

7.  External  orbital  gyrus  is  that  part  of  the  orbital  surface  which  lies  out- 
side of  the  triradiate  sulcus. 

8.  The  frontal  gyri,  three  gyri  which  compose  the  superior  and  lateral 
surface  of  the  frontal  lobe  of  the  cerebrum,  all  lying  in  front  of  the  ascending 
frontal  gyrus.  They  are  denned  by  the  superior  and  inferior  frontal  sulci,  and 
by  the  vertical  fissure  or  precental  sulcus. 

9.  The  hippocampal  gyrus  is  the  continuation  of  the  gyrus  fornicatus 
where  it  dips  down  behind  and  below  the  corpus  callosum,  and  continues  for- 
ward to  the  uncinate  gyrus:  so-called  from   its  relation   to   the  hippocampus. 


346 


ANATOMY    IN    A    NUTSHELL. 


10.  That  part  of  the  first  frontal  convolution  which  appears  on  the  median 
side  of  the  hemisphere  is  the  marginal  gyrus,  or  it  is  that  gyrus  which  arches 
over  the  extremity  of  the  fissure  of  Sylvius. 

11.  Occipital  gvri  are  the  three  principal  convolutions  of  the  occipital  lobe 
of  the  cerebrum,  separated  by  two  small  transverse  sulci,  and  distinguished  as 
first,  second,  and  third;  from  above  downward,  superior,  middle,  and  inferior. 

12.  The  orbital  gyri  are  upon  the  under  or  orbital  surface  of  the  frontal 
Lobe  <>!'  the  cerebrum,  which  rest  upon  the  orbital  plate  of  the  frontal  bone. 
They  are  three  in  number,  directly  continuous  with  and  corresponding  to  the 
frontal  gyri.  The  two  which  are  best  marked  are  sometimes  called  internal 
and  external. 

13.  The  parietal  gyri  are  four  well-marked  convolutions  upon  the  superior 

PLATE  CLXVI. 


MEDULLA  OBLONGATA 


OPTIC   THALAMUS 


EPENCEPHALON 


TERMINALS   \  OLFACTORY  DIVERTICULUM 


CEREBRAL    HEMISPHERE 


& 


MID    BRAIN  FORAMEN  OF  MONRO 


A  Horizontal  Section  of  a  Vertebrate  Brain. 


and  lateral  surface  of  the  parietal  lobe;  and  especially  two  of  these  distinguished 
as  the  ascending  parietal  or  posterior  central  and  the  superior  parietal,  the 
other  two  being  commonly  known  as  the  supramarginal  and  angular  gyrus. 

14.  Quadrate,  or  quadrate  gyrus,  is  a  convolution  of  somewhat  square 
figure  appearing  on  the  median  surface  of  the  cerebrum  between  the  callosum 
marginal  sulcus  in  front  and  the  parietooccipital  sulcus  behind,  and  continu- 
ous below  with  the  gyrus  fornicatus,  also  called  precuneus. 

L5.  Sigmoid  gyrus  is  the  somewhat  S-shaped  fold  which  curves  about  the 
Lateral  end  of  the  cruciate  fissure  and  whose  surface  includes  several  constant 
and  well-marked  "motor  areas." 

lii.  The  temporal  gyri,  a  general  name  of  the  temporal  convolutions. 

17.  Uncinate  gyrus  is  in  the  median  surface  of  the  cerebrum  nearly  op- 
posite the  gyrus  fornicatus. 

Is.    Gyri  operti  ("covered  gyrus")  is  the  insula. 

L9.  The  dentate  gyrus  is  lodged  in  the  hippocampus  fissure,  and  is  a  long 
slender  roll  of  gray  substance,  notched  upon  its  exposed  surface. 


ANATOMY    IN    A    NUTSHELL. 


347 


LESSON  C. 

Besides  the  gray  matter  of  the  cerebral  hemispheres  of  the  cerebellum  and 
the  meddulla  oblongata,  and  the  ganglia  at  the  base  of  the  brain  are: 

(a)  Olfactory  bulb  which  is  the  anterior  enlargement  of  the  olfactory- 
tract  from  the  which  olfactory  nerves  are  sent  off. 

(b)  Corpora  striata  (striped  bodies)  are  large  ganglia  of  the  brain,  of  mixed 
white  and  gray  substance,  situated  beneath  the  anterior  horn  of  each  lateral 
ventricle  of  the  cerebrum. 

(c)  Optic  thalamus  is  a  large  ganglion  of  the  thalamencephalon,  situated 
upon  the  crus  and  separated  from  the  lenticular  nucleus  by  the  internal  cap- 
sule; also  called  thalamus.  It  gives  origin  to  some  of  the  fibers  of  the  optic 
nerve. 

(d)  Tubercula  quadrigemina  are  on  the  dorsal  part  of  the  mid-brain. 
The  lobes  are  paired,  right  and  left,  and  hence  called  corpora  bigemina  in  ani- 

PLATE    CLXVII. 


PINEAL      BODY  fe 

CORPRA    QUADRIGEMINA 
CEREBELLUM 


%, 


MEDULLA  OBLONGATA 


OLFACTORY  DIVERTICULUM 


THALAMUS 


A  Sagitaal  Section  of  a  Vertebrate  Brain. 

mals  below  mammals.  In  man  they  are  marked  by  a  cross-furrow  so  they  are 
called  corpora  quadrigemina,  and  constitutute  what  are  called  the  nates  or 
testes  of  the  brain.     The  optic  nerve  arises  in  part  from  the  optic  lobes. 

(e)  Tuber  annulare  is  the  annular  tuber  of  the  brain,  the  pons  Varolii. 

The  anterior  commissure  is  white  and  situated  directly  in  front  of  the  an- 
terior pillars  of  the  fornix.  (Plate  CLXXX).  It  connects  those  parts  of  the 
hemispheres  not  connected  by  the  corpus  callosum,  viz.,  in  man  the  temporal 
lobes  and  in  osmaties  the  entire  rhinencephalon.  It  forms  a  curve  with  the 
convexity  forward  and  slightly  upward  and  its  extremities  are  spread  on!  Ian- 
shaped.  Its  center  forms  the  anterior  boundary  of  the  third  ventricle  between 
the  anterior  pillars  of  the  fornix.  It  passes  beneath  or  through  the  bead  of 
the  caudate  nucleus  and  the  posterior  two-thirds  of  the  lenticular  nucleus  where 
it  is  spread  out  in  the  substance  of  the  temporal  lobe.  The  A.NTERIOB  com- 
missure is  a  more  primitive  commissure  than  the  corpus  callosum   and  de- 


348 


ANATOMY    IN    A    NUTSHELL. 


creases  in  size  as  the  corpus  callosum  increases.  The  anterior  fibers  of  the  an- 
terior commissure  (pars  olfactoria)  connect  the  olfactory  bulbs  of  opposite  sides 
and  in  man  is  very  small,  but  in  osmatics  it  is  large,  being  twice  as  large  as  the 
posterior  portion  or  hemispheral  bundle  of  fibers.  This  anterior  portion  is  large 
in  fishes.  The  posterior  portion  of  the  anterior  commissure  connects  the  tem- 
poral lobes  and  the  amygdalae  nucleus  of  opposite  sides.  The  middle  fibers 
pas  through  the  olfactory  bulb  of  one  side  to  the  temporal  lobe  of  the  opposite 
side.  Thus  we  may  have  a  lesion  on  one  temporal  lobe  producing  loss  of  smell 
of  the  opposite  side  of  the  nose  called  crossed  anosmia. 

The  middle  or  soft  commissure  is  gray;  it  is  very  delicate,  though  some- 
time- it  is  double.     It  connects  the  two  optic  thalami,  which  takes  place  about 

PLATE  CLXVI1I. 


EPIPHYSIS 


CORPORA    QUAORIGEMINA 


5TH    VENTRICLE 

IN 
SEPTUM  LUCIDUM 


FORAMEN     Of    MONRO 

HYPOPHYSIS 


A  Sagittal  Section  of  the  Brain. 

the  fifth  month  of  intra-uterine  life.  It  is  not  really  a  commissure  as  no  fibers 
pass  from  it  from  one  side  of  the  brain  to  the  other. 

The  posterior  commissure  is  white  and  is  situated  behind  the  upper  end  of 
the  aquedud  of  Sylvius.  It  forms  part  of  the  posterior  boundary  of  the  third 
ventricle.  The  pineal  gland  is  just  above  and  slightly  posterior  to  it.  Most 
of  the  fibers  of  this  commissure  are  a  continuation  of  the  fibres  of  the  fillet, 
which  after  decussation,  pass  through  the  optic  thalamus  into  the  corona  radiata 
of  the  opposite  side.  The  anterior  fibres  pass  from  the  root  of  the  pineal  gland 
to  the  nucleus  of  the  trigonum  habenulse  on  one  side  and  the  nucleus  of  the 
third  nerve  of  the  opposite  side. 

The  fornix  is  composed  of   Longitudinally   arched    bundles   of   fibers.     It 


1 


ANATOMY    IN    A    NUTSHELL. 


349 


consists  of  a  body  and  two  anterior  pillars  and  two  posterior  pillars  .  It  is  sit- 
uated just  beneath  the  corpus  callosum. its  posterior  part  being  attached  to  the 
corpus  callosum.  The  body  is  triangular  with  the  apex  in  front  and  base  be- 
hind. It  forms  one  of  the  boundaries  of  the  roof  of  the  third  ventricle  and  part 
of  the  floor  of  the  lateral  ventricle.  The  anterior  pillars  or  columx.e  for- 
NICES,  descend  from  the  gray  matter  of  the  third  ventricle  behind  the  anterior 
commissure  and  in  front  of  the  foramen  of  Monro.  As  they  descend  they 
spread  out.  leaving  an  interval  which  is  occupied  by  the  septum  lucidum. 
They  receive  reinforcements  from  the  tsenia  semicircularis  and  the  crura  of 
the  pineal  gland  and  the  septum  lucidum.     They  form  loops  around  the  cor- 

PLATE  CLXIX. 

GREAT     LONGITUDINAL     FISSURE 


j&M 


OLFACTORY  TRACT 

A  Coronal  Section  Through  the  Anterior  Horns  of  the  Lateral 

Ventricles. 

jiora  albicantia,  making  the  stroma  zonale  or  white  portion.-  of  these  bodies. 
Fibres  continue  from  the  corpora  albicantia  and  the  optic  thalamus  called 
filn  rs  of  Vizq'd'azyr.  The  posterior  pill  uts  of  the  fornix  descend  from  the  sides 
of  the  body  of  the  fornix  and  between  the  diverging  crura  and  the  splenium  of  the 

corpus  callosum  is  the  psalterium  or  lyra  consisting  of  white  matter  and  having 

on  its  surface  some  transverse  oblique,  and  longitudinal  line-.  From  it-  fancied 
''  semblance  to  the  strings  of  a  harp  this  area  is  called  a  lyra.  Bach  pillar 
passes  around  the  pulvinar  of  the  optic  thalamus  and  then  descends  in  the 
descending  horn  of  the  lateral  ventricle.  While  there  they  send  libers  t<>  the 
hippocampus  major  ami  end  in  the  gyrus  hippocampus  and  the  uncinate  gyrus. 
The  corpus  callosum   (callous  body)   is  the  great    white  commissure  of  the 


350 


ANATOMY    IN  A    NUTSHELL. 


hemisphere  of  the  brain:  the  commissure  magna  or  trabs  cerebri.  This  struc- 
ture is  peculiar  to  the  mammalia;  it  is  first  found  in  a  rudimentary  state  in  the 
implacentals,  and  increases  in  size  and  complexity  to  the  highest  mammals, 
coincidentally  with  a  degree  of  other  special  cerebral  commissures.  It  is  also 
called  callosum. 

The  corpus  callosum  connects  the  frontal,  parietal,  central  and  occipital 
lobes.  It  is  the  great  transverse  commissure  of  the  brain.  It  is  three  and 
one-half  inches  long  on  the  superior  surface  and  two  and  one-half  inches  on  the 
inferior.  It  extends  within  one  and  one-fourth  inches  of  the  anterior  boundary 
<>f  the  brain  and  within  two  inches  of  the  posterior  boundary  of  the  brain.     It 

PLATE  CLXX. 


BODY  Cr  LATERAL  VENTRICLE. 


CHOROID  PLEXUS- 


0F  CAUDATE  NUCLEUS 


EXTERNAL  CAPSULE 


OPTIC  TRACT 
HlPPOCAMPAL  FISSURE  „ur..  uri„  ALBICANTIA 

A  Coronal  Section  Through  Middle  Commissure  of  Brain. 


is  convex  above  and  concave  below,  thinner  in  the  center  of  body  than  at  either 
end.  Tin:  posteriob  end  is  called  the  splenium  or  ped.  The  anterior  end 
which  is  between  the  frontal  lobes  is  called  the  genu  or  Knee.  The  rostrum  is 
the  continuation  of  the  genu  and  joins  the  lamina  cinerea.  On  the  superior 
surface  a  groove  extends  along  the  median  line  called  the  raphe  and  on  each 
side  of  tlii-  are  the  stride  longitudinales  or  nerves  of  Lancisi.  These 
nerves  are  two  distind  white  bands  given  off  to  the  termination  of  the  corpus 
callosum  and  culled  the  peduncles  of  the  corpus  callosum.  They  pass  across 
the  anterior  perforated  space  to  end  in  the  temporal  lobes,  uniting  with  the 
inner  root  of  the  olfactory  tract.     The  forceps  minor  are  fibers  which  go  for- 


ANATOMY    IN    A    NUTSHELL. 


351 


ward  from  the  anterior  and  lateral  angles  into  the  frontal  lobes.  The  forceps 
major  are  fibers  which  continue  backward  through  the  posterior  angles  into  the 
occipital  lobe. 


LESSON  CI. 

The  septum  lucidum  forms  the  inner  boundary  of  the  lateral  ventricle  and 
unites  in  front  with  the  genu  and  rostrum  of  the  corpus  callosum.  Posteriorly 
and  inferiorly  it  is  united  with  the  fornix  and  its  anterior  peduncles.  (Plate 
CLXXXIV).  It  consists  of  two  laminae  which  enclose  the  fifth  ventricle.   It  is 

PLATE  CLXXI. 


LATERAL      SINUS 

A  Coronal  Section  Through  the  Posterior  Horns  of  Lateral  Ventricles. 

a  triangular  area  of  gray  matter.  This  ventricle  was  originally  a  part  of  the 
great  longitudinal  fissure  but  the  two  hemispheres  are  united  above  by  the  cor- 
pus callosum  and  below  by  the  fornix,  and  the  space  betwe<  ;>  them  becames  a 
distinct  cavity  with  walls  of  its  own — lamina1  or  septum  Lucidum.  The  Loner 
layer  is  gray,  middle  white,  and  external  one  ependymal  or  ependyml  tissue 
covered  by  the  epithelial  layer  continuous  with  that  lining  the  lateral  ventricle. 
Velum  interpositum  or  tela  choroidea  superior  the  word  tela  means  a  web 
and  is  applied  to  a  membrane  formed  by  the  position  of  the  pia  mater  and 
ependyma  when  the  intervening  layer  of  nerve  tissue  has  disappeared.  It  is 
a  triangular  process  of  pia  mater  which  is  prolonged  through  the  transverse 
fissure  and  lies  over  the  third  ventricle  and  upper  surface  of  the  op1  ic  thalamus. 
from  its  under  surface  it  supplies  two  vascular    processes    which    form   the 


352 


ANATOMY    IN    A    NUTSHELL. 


choroid  plexus  of  the  third  ventricle  and  each,  side  the  choroid  plexus  of  the 
lateral  ventricles  are  formed. 

The  optic  thalami  are  mostly  gray  matter  but  are  white  exterally  and  are 
situated  above  the  tegmentum  of  the  cms.  The  inner  surface  of  each  forms  the 
lateral  bounary  of  the  third  ventricle  and  the  upper  suiface  forms  part  of  the 
floor  of  the  lateral  ventricle. 

The  internal  capsule  (fibres  of  the  crusta  or  pes)  separate  the  outer  sur- 
face of  each  optic  thalamus  from  the  lenticular  nucleus.  Each  optic  thalamus 
has  four  surfaces.  (1)  superior  or  dorsal  (2)  inferior  or  ventral,  (3)  internal  or 
mesial,   and   (4)   external  or  lateral.     The  taenia   semicircularis  separates  the 

PLATE  CLXXI1. 


POSTERIOR  CORNU 


FORAMEN  OF  MONRO 


ANTERIOR  CORNU 


A  Cast  of  the  Ventricles  of  the  Brain. 

superior  surface  from  the  caudate  nucleus.  This  surface  is  divided  by  the 
sulcus  choroidens  into  mesial  and  lateral  portions.  The  lateral  portion  of  this 
depression  is  in  the  floor  of  the  lateral  ventricle.  Anteriorly  it  grows  into  a 
prominence,  the  anterior  tubercle.  The  superior  surface  is  separated  from  the 
mesial  surface  by  the  peduncles  of  the  pineal  gland.  The  posterior  surface 
divides  into  a  large  prominence,  the  pulvinar.  The  trigonum  habenulae  is  a 
depressed  area  of  gray  matter  between  the  pulvinar  and  the  beginning  of  the 
peduncles  of  the  pineal  gland.  The  ganglia  of  habenulae  is  anterior  to  the  tri- 
gonum habenulae. 

The  internal  and  external  geniculate  bodies  are  elevations  of  gray  matter 
on  the  posterior  and  inferior  surface  of  the  pulvinar.  The  internal  geniculate 
body  is  situated  on  the  inferior  and  inner  side  of  the  pulvinar,  between  the 
brachia  of  the  corpora  quadrigemina.  It  is  covered" with  a  layer  of  white  fibers. 
The  external  geniculate  body  is  below  and  external  to  the  internal  geniculate. 


ANATOMY    IN    A    NUTSHELL. 


353 


It  is  of  a  yellowish-gray  color.     The  projection  system  of  fibers  which  pass 
through  the  internal  capsule  and  bundles  are  the  peduncles  of  the  optic  thala- 


mus 


The  pineal  gland,  also  called  conarium  and  epiplysis,  is  a  small  reddish  body 

PLATE  CLXXIII. 

ANT   COMMUNICATING  A 


CIRCLE  OF  WILLIS  AND  ARTERIES  OF  BRAIN. 

The  Circle  of  Willis. 

developed  from  the  hind*  r  par!  of  the  roof  of  the  first  cerebral  vesicle,  and  lying 
in  front  of  and  above  the  nates.  Its  substance  consists  mainly  of  epithelial 
follicles  and  connective  tissue;  there  is  no  evidence  thai  it  is  a  nervous  struc- 
ture, and  its  t'nnction.if  it  possesses  anv.is  unknown.  It  was  formerly  supposed 
by  some  (as  the  Cartesians)  to  be  the  scat  of  the  soul.     (Plate  CL XXX). 


354 


ANATOMY    IN    A    NUTSHELL 


Then'  arc  numerous  peduncles  of  the  brain.  Those  of  the  cerebellum  are 
three  pairs  and  are  stout  bundles  of  nerve  fibres  which  connect  the  cerebellum 
with  other  chief  divisions  of  the  brain.  They  are  distinguished  by  their  posi- 
tion as  superior,  middle,  and  inferior  peduncles  or  crura.  The  superior  pair 
emerge  from  the  mesial  part  of  the  medullary  substance  of  the  hemispheres,  and 
run  forward  upward  to  reach  the  nuclei  tegmenti  of  the  opposite  sides,  after 
decussation  under  the  formatio  reticularis.  Also  called  (1)  crura  ad  corpora 
quadrigemina,  (2)  crura  ad  cerebrum,  (3)  processus  cerebelli  ad  cerebrum,  (4) 
processus-e-cerebello  ad  testes.  (.">)  branchia  conjunctiva,  and  (6)  branchia  con- 
junctoria).     (Plate  CLXXXVIII). 

PLATE  CLXXIV. 


Showing;  Blood  Supply  of  the  External  Surface  of  the  Brain. 

The  middle  pair  from  the  ventral  transverse  fibres  of  the  pons,  emerging 
from  the  lateral  part  of  the  white  substance  of  the  hemispheres.  (Also  called 
crura  or  processus  ad  uiedullani).     (Plate  CLXXXVIII). 


LESSON  CI  I. 

The  fissures  of  the  cerebellum  are  three  in  number — two  vertical  and  one 
horizontal.  The  great  horizontal  fissure  is  a  continuous  fissure  which  separates 
the  cerebellum  into  upper  and  lower  portions.  It  begins  in  front  at  the  middle 
peduncles,  and  extend-  around  the  outer  and  posterior  border  of  each  hemi- 
sphere. 

The  vertical  ones  are  : 

1.  Incisura  cerebelli  anterior,  the  anterior  median  notch  of  the  cerebellum, 
into  which  the  corpora  quadrigemina  arc  received. 

2.  Incisura  cerebelli  posterior,  the  median  notch  on  the  posterior  outline 
of  the  cerebellum,  formed  by  the  projection  of  the  cerebellar  hemispheres  be- 
yond  the   vermis.      (Plate  CLXXXVIII). 


ANATOMY    IN    A    NUTSHELL. 


255 


The  vermis  is  the  median  lobe  of  the  cerebellum;  the  vermiform  process  of 
the  cerebellum  is  divided  into  the  prevermis  and  the  postvermis. 

The  olivary  body  is  the  ganglion  of  the  oblongata  lying  on  either  side  just 
lateral  of  the  pyramid,  and  forming  an  oval  projection  on  the  surface  just  below 
the  pons.  It  consists  of  the  nucleus  olivaris  inferior  with  a  covering  and  filling 
of  white  matter,  also  called  inferior  olivary  body,  or  inferior  olive,  and  corpus 
semiovale. 

The  corpus  dentatum  is  (a)  a  plicated  capsule  of  gray  matter,  open  an- 
teriorily,  situated  within  the  white  substance  of  each  cerebellar  hemisphere. 
Also  called  ganglion  of  the  cerebellum  and  nucleus  dentatus.  (b)  A  somewhat 
similar  mass  of  gray  matter  in  each  olivary  body.     Also  called  corpus  ciliare. 

PLATE  CLXXV. 


FISSURE  OF  ROLANDO. 


PERFORATING  BRANCHES 


MIDDLE     CEREBRAL  A.  IN  FISSURE.      OF  SYLVIUS. 

Showing  Distribution  of  Middle  Cerebral  Artery. 

The  lateral  tract  is  continuous  with  the  lateral  column  of  the  spinal  cord, 
lies  behind  the  olivary  body  and  in  front  of  the  restiform. 

The  restiform  body  is  the  inferior  peduncle  of  the  cerebellum,  by  which  it 
connects  with  the  oblongata  and  parts  below.  It  contains  the  direcl  cere- 
bellar-tract  fibres, crossed  and  uncrossed  from  the  posterior  columns  of  thecord, 
and  fibres  from  the  centra-lateral  (lower)  olive  . 

The  fillet  is  some  special  bundle  of  nerve-fibres;  especially,  a  band  of  Longi- 
tudinal fibres  lying  in  the  ventral  and  outer  parts  of  the  tegmental  region  of 
the  brain.  Its  distribution  is  not  known,  bu1  it  seems  to  conned  below  with  the 
posterior  columns  of  the  spinal  cord  and  above  with  the  corpora  quadrigemina, 
optic  thalami,  lenticular  nucleus,  and  cortex  cerebri.     It  is  also  called  lemniscus. 

A  vesicle  is  a  small,  bladder-like  structure,  cavity  cell,  or  the  like,  in  a  body. 
There  are  three  vesicles  in  the  brain,  anterior,  middle,  and  posterior.     They  are 


356 


ANATOMY    IN    A    NUTSHELL. 


I 


embryonic  and  so  transitory,  and  have  other  names  when  matured  They  are 
called  anterior,  middle,  and  posterior,  corresponding  to  the  fore-brain,  mid- 
braiD  ^d  hind-brain.  They  are  pmnitive  structures  and  become  the  ven- 
tricles of  the  brain.     The  three   commonly  form   five  by  the   subdivision  of 

'  Tbe  septum  lucidum  is  the  median  partition  of  the  lateral  ventricles  of  the 
,„,„,.  ^dosing  the  camera,  pseudocele,  or  so-called  fifth  ventricle.  Also  called 
,,,  septum  pellucidum,  (2)  septum  medium,  (3)  septum  ventnculorum,  (4) 
ventricular  septum.   (5)  septum  medullare  tnangulare. 

The  fornix  is  an  arch.  In  the  human  brain  it  consists  of  two  Longitudinal 
bundles  of  fibres,  one  on  each  side,  which  rise  from  the  corpora  albicantia  pass 
up.  as  the  anteriob  pillars  of  the  fornix  in  front  of  the  foramina  of  Monro 

PLATE  CLXXVI. 


ARR  SUPPl.kD  BY  M  D3LE  CEREBRAL  ARTERY. 

Showing  Blood  Supply  on  Mesial  Surface,  (Sagittal  Section^f  Brain). 
and  behmd  the  anterior  commissure,  these  somewhat  flattened  and  in  apposi- 
tion to  each  other,  arch  backward  beneath  the  corpus  callosum  and  above  the 
velum  interpositum,  forming  the  body  of  the  fornix  and  then  diverge  toward 
the  back  pari  of  die  corpus  callosum,  to  turn  down,  as  the  posteriok  pillars 
0f  the  fornix  (crura  fornices),  into  the  floor  of  the  descending  cornua  of  the 
lateral  ventricles,  where  their  free  edges  form  the  fimbriae. 

The  fimbria  is  a  narrow  band  of  white  fibres  running  along  the  median 
concave  side  of  the  hippocampus  major.  It  is  a  continuation  of  the  pillars  of 
the  fornix.     Also  called  taenia  hippocampa  and  corpus  fimbriatum. 

The  taenia  semilunaris  consists  of  commissural  fibres  between  the  corpus 
striatum  and  the  optic  thalamus. 

The  cerebrum  is  thai  portion  of  the  brain  which  lies  in  front  of  the  cere- 
bellum ami  pons  Varolii.  It  comprises  aboul  seven-eighths  of  the  weight  oi 
the  brain.     It  is  the  center  of  intelligence  and  thought  . 


ANATOMY    IX    A    NUTSHELL. 


357 


The  cerebellum  is  called  the  arbor-vita1  or  tree  of  life.  It  is  the  center  for 
the  control  of  muscles.  It  is  between  the  corpora  qnadrigemina  in  front  and 
the  medulla  oblongata  behind,  and  forming  part  of  the  roof  of  the  fourth  ven- 
tricle. 

The  pons,  also  called  pons  Varolii  and  pons  cerebelli,  is  a  great  transverse 
commissure  seen  at  the  base  of  the  brain  in  front  of  the  medulla.  Its  fibres 
connect  the  hemispheres  of  the  cerebellum  with  each  other  and  the  medulla. 

The  medulla  oblongata  is  (a)  marrow;  (b)  the  so-called  spinal  nervous  sys- 
tem; the  myelon;  more  fully  called  medulla  spinalis:  (c)  the  hindmost  segment 
of  the  brain,  continuous  with  the  spinal  cord. 

PLATE  CLXXVII. 


area  supplied  by  middle  cerebral  artery. 
Showing  Blood  Supply  at  Base  of  Brain. 

A  ventricle  (literally  a  belly,  a  stomach)  is  a  small  cavity.  Those  of  the 
brain  are  a  series  of  connecting  cavities,  containing  fluids,  within  the  brain, 
continuous  with  the  central  cavity  of  the  spinal  cord.  They  are  the  remains 
of  the  original  neural  canal,  formed  by  a  folding  over  of  the  epiblast. 

The  optic  commissure  or  chiasma,  somewhat  quadrilateral  in  form,  rests 
upon  the  optic  groove  of  the  sphenoid  bone,  being  bounded,  above,  by  the 
lamina  cinerea;  behind,  by  the  tuber  cinereum;  on  either  side,  by  the  anterior 
perforated  -pace.  Within  the  commissure  the  optic  nerves  of  the  two  sides 
undergo  a  partial  decussation.  The  fibres  which  form  the  inner  margin  (in- 
ferior commissure  of  Gudden)  of  each  trad  are  continuous  across  from  one  to 
the  other  side  of  the  brain.  These  may  be  regarded  as  commissural  fibres 
(intercerebral)  between  the  interna]  geniculate  bodies.  Some  fibres  are  con- 
tinued across  the  anterior  border  of  the  chiasma,  and  connect  the  optic  uerves 
of  the  two  sides,  having  no  relation  with  the  optic  tracts.  They  may  be  re- 
garded as  commissural  fibres  between  the  two  retinae  (inter-retinal  fibres'). 
The  outer  fibres  of  each  tract  are  continued  into  the  optic  nerve  of  the  -nine  side. 


358 


ANATOMY    IN   A    NUTSHELL. 


The  central  fibres  of  each  tract  are  continued  into  the  optic  nerve  of  the  opposite 
side,  decussating  in  the  commissure  with  similar  fibres  of  the  opposite  tract. 
The  ventricles  arc  two  lateral,  third  ventricle,  fourth  ventricle, 

FIFTH    \  ENTRICLE,   and  THE  VENTRICLE  OF  THE  CORPUS  CALLOSUM. 

The  lateral  ventricles  arc  found  one  in  each  hemisphere;  they  communicate 
with  each  other  and  with  the  third  ventricle  through  the  foramen  of  Monro. 

PLATE  CLXXVIII. 


NINTH 
TENTH 

AND  ELEVENTH 


LIGAMENTMM  DENTICULATUM 


Showing  Falx  Cerebri,  Etc. 

The  third  ventricle  lie-  between  the  optic  thalami.  It  communicates  with  the 
fourth  ventricle  through  the  aqueduct  of  Sylvius.  The  fourth  ventricle/lies 
between  the  cerebellum  and  the  pons  and  medulla.  The  so-called  fifth  ven- 
tricle, (n-  pgeudocele,  has  no  connection  with  the  other  cerebral  ventricles,  being 
of  a  different  nature  and  simply  a  small  interval  between  the  right  and  left 
layers  of  the  septum  lucidum. 


ANATOMY    IN    A   NUTSHELL. 


359 


LESSON  cm. 

The  Medulla  Oblongata  is  about  one  and  one-half  inches  long  and  three- 
fourths  of  an  inch  wide  and  one-half  of  an  inch  antero-posteriorily.  It  extends 
from  the  foramen  magnum  inferiorly  to  the  pons  superiority.  It  is  the  smallest 
part  of  the  main  divisions  of  the  brain  but  the  largest  from  a  physiological 
standpoint.  It  has  five  main  centers  in  it,  viz.,  (1)  Respiratory,  (2)  Cardio- 
inhibitory,  (3)  Vasomotor,  (4)  Diabetic,  and  (5)  Salivary.    (Plate  CLXXXV1I). 

PLATE  CLXXIX. 


OLFACTORY   BULB 

OPTIC    NERVE 
OPTIC      COMMISSURE 

|NT.  CAROTID    ARTERY 
THIRD  N 
FOURTH    N 
SIXTH  N 
AUDITORY  ARTERY, 
.AUDITORY  AND  FACIAL 
SUPERIOR  PETROSAL 
INFERIOR    PETROSAL 

STRAIGHT    SINUS. 

TORCULAR        HEROPHlLl 


>jPERI0R  LONGITUDINAL  SINUS. 


OPHTHALMIC        VEIN- 


CAVERNOUS  SINUS. 


OPHTHALMIC  DIVISION 
OF  FIFTH  N 


BASILAR     A 

VERTEBRAL     A. 
ANTERIOR     SPINAL     A. 
GLOSSOPHARYNGEAL 

AND     PNEUMOGASTRIC 

HYPOGLOSSAL 


SPINAL   ACCESSORY 
OCCIPITAL  SINUS 


RIGHT    LATERAL    SINUS, 


Sinuses  at  the  Base  of  the  Brain. 

It  is  gray  on  the  outer  side  and  white  on  the  inner.  Its  posterior  SUR- 
FACE makes  the  lower  part  of  the  anterior  boundary  or  the  floor  of  the  fourth 
ventricle.  Its  anterior  surface  rests  upon  the  basilar  process  of  theoccipital 
bone.  In  the  median  line  of  the  anterior  surface  is  the  antero-median  fissure 
which  is  continuous  with  the  antero-median  fissure  of  the  cord.  On  each  side 
of  this  fissure  there  is  a  pyramid.  This  pyramid  has  fibres  next  to  the  fissure 
which  are  derived  from  the  crossed  pyramidal  tracts  after  they  push  the  gray 
matter  of  the  anterior  horn  of  the  cord  superficially.  Next  to  this  it  has  the 
fibres  of  the  direct  pyramidal  tract.  External  to  the  pyramid  we  have  the 
olivary  body  superiority  and  the  lateral  tract  infcriorily.     This  olivary  body  has 


360 


ANATOMY    IN    A    NUTSHELL. 


the  inferior  olivary  nucleus  and  the  dentates  nucleus.  The  olivary  nucleus  is 
hollow  and  gives  off,  from  an  opening  in  its  side,  little  fibres  called  the  ped- 
uncles of  the  olivary  body.  Next  to  the  olivary  and  lateral  tract  external  we 
have  part  of  the  restiform  body.  Another  name  for  the  restiform  body  is  in- 
ferior pedicles  of  the  cerebellum.  The  posterior  surface  of  the  medulla  has  the 
postero-median  fissure  and  on  each  side'  of  it  is  (1)  the  funiculus  gracilis, 
(2)  funiculus  cuneatus,  (3)  the  funiculus  Rolando.  (4)  lateral  tract.  The 
upper  portion  of  the  posterior  surface  makes  the  restiform  body  or  the  inferior 
peduncles  of  the  cerebellum. 


PLATE  CLXXX. 


POST.  COMMISSURE. 


EPIPHYSIS      OR 
PINEAL  GLAND. 


SPLENIUM  OF  CORPUS  CALLQSUM 


ANTvCOMMISSURE. 

U  "^FORAMEN  OF  MONRO. 
OPTIC  NERVE. 


INFUNDIBULUM. 


HYPOPHYSIS     OR 
PITUITARY  BODY. 


A  Sagittal  Section  of  Brain,  Showing  the  Third  and  Fourth  Ventricles 


The  fibres  in  the  cold  which  travel  through  the  direct  cerebellar  tract, 
which  is  in  the  lateral  column  of  the  cord,  pass  up  into  the  medulla  into  the  resti- 
form body,  instead  of  passing  straight  into  the  lateral  column.  The  funiculus 
Rolando  is  a  continuation  of  the  gray  matter  from  the  posterior  horn  of  the 
cord,  where  it  is  called  substantia  gelatinosa  Rolando,  up  into  the  medulla 
where  it  is  situated  between  the  funiculus  cuneatus  and  lateral  column. 

Cerebellum  (little  brain)  is  about  one-tenth  of  the  entire  brain.  It  weighs 
about  five  ounces.     It  is  about  one-eighth  as  large  as  the  cerebrum  in  the  adult. 

In  early  child] 1  it  may  he  as  small  as  one-twentieth  of  the  cerebrum.     It  is 

situated  in  the  posterior  fossa  at  the  base  of  the  skull,  being  separated  from  the 
cerebrum  by  the  tentorium  cerebelli.  It  consists  of  two  hemispheres  connected 
by   the  worm   (vermiform  process).     The  medulla  is  situated  in  the  anterior 


ANATOMY    IN    A    NUTSHELL. 


361 


inferior  portion  in  a  groove  called  the  vallecula.  The  falx  cerebelli  is  situated 
in  a  groove  posterior  to  the  worm  between  the  two  hemispheres.  The  hemi- 
spheres have  fissures  like  the  cerebrum  but  do  not  have  convolutions  like  the 
cerebium  but  instead  have  folia.  The  cerebellum  is  gray  on  the  outer  side  and 
white  on  the  inner  side.  It  forms  the  roof  or  posterior  boundary  of  the  fourth 
ventricle. 

PLATE  CLXXXL 


CORPORA 
QUADRIGEMINA 


TRACT 
SUPERIOR 
CEREBELLAR 
PEDUNCLE 
FOURTH 
VENTRI  CLE     — ^?^^^^x(^^^n; 
HIDDLE  CEREBELLAR  %:^2§f*73 


PEDUNCLE -^>    ^%l\\       ^    fMl 


EIGHTH  NERVE  NUCLEUS 


INFERIOR     CEREBELLAR     PEDUNCLE    - 


A  Sagittal  Section  of  Brain  Showing  Fibers. 


The  worm,  commencing  with  the  anterior  superior  part,  and  passing 

backward  consists  op  the  following  parts: 

Frenulum 


(1)  Lingular 

Precentral  fissure 


Fraenulum 


Ala  lobulus  centralis 


(2)    Lobulus  centralis         Ala  lobulus  centralis 
Post-central  fissure 


Anterior  crescentic-lobule       (3)  Oilmen  monticuli       Anterior  crescentic  lobule 

Preclival  fissure 


Posterior  erescentic  lobule     (4)  Clivus 

Post-clival  fissure 


Posterior   erescentic 
lobule. 


Posterior  superior  lobule        (5)   Folium  cacuminis         Posterior  superior  lobule 


3(52 


ANATOMY    IN    A    NUTSHELL. 


The  lower  worm  from  before  backward  consists  of  the  following 
parts: 

Flocculus  (1)  Nodule  Flocculus 

Amygdala  (2)   Uvula  Amygadala 

BiventraJ  (3)  Pyramid  Biventral 


Sledner  lobe 
Post-gracile  fissure 
Postero-inf  erior  lobe 

(Inferior  semilunar) 


(4)  Tuber  valvulae 


Slender  lobe 
Post-gracile  fissure 
Postero-inf  erior  lobe 
(Inferior  semilunar) 


There  are  four  sets  of  gray  nuclei  in  the  white  matter  of  each  hemisphere 
called  (1)  Corpus  dentatum.  (2)  Nucleus  emboliformis.  (3)  Nucleus  globosis. 
I  h   Nucleus  fastigii.     (Plate  CLNXI). 

PLATE  CLXXXII. 


A  Sagittal  Section  of  Brain,  Showing  Centers  of  Smell  and  Taste. 

The  cerebellum  has  three  sets  of  peduncles,  the  superior  ones  pass  from 
the  cerebellum  to  the  corpora  quadrigemina  (processes-e-cerebelli  ad  testes) 
and  have  efferent  fibres  in  them.*  The  middle  ones  connect  the  middle  part 
of  the  cerebellum  with  the  pons  and  have  both  afferent  and  efferent  fibres.  The 
[NFERIOK  ONES  connect  the  cerebrum  with  the  cord  and  are  called  the  restiform 
bodies. 


LESSON  CIV. 

The  pons  is  the  connecting  link  for  the  other  parts  of  the  brain.  It  is  con- 
nected to  the  cerebellumby  the  middle  peduncles  of  the  cerebellum.  It  is  con- 
nected to  the  cerebrum  by  the  crus  cerebri  or  the  peduncles  of  the  cerebrum. 
It  is  connected  to  the  medulla  by  fibres  through  the  pyramidal  tract.  It  is 
situated  on  the  basilar  process  of  the  occipital  bone  and  the  posterior  part  of 
the  sphenoid  bone.      It  is  one  inch  long  and  one  and  one-half  inches  wide.     Its 

♦There  are  afferent  fibres  immediately  beneath  the  superior  peduncle  in  the  valve  of  Vieussens. 


ANATOMY    IX    A    NUTSHELL. 


363 


anterior  surface  is  convex  from  side  to  side  and  slightly  convex  from  above 
downward.  Its  superior  border  is  longer  than  the  lower  border  and  Is  convex, 
while  the  lower  border  Is  almost  straight.  In  the  median  line  on  the  anterior 
surface  there  is  a  groove  for  the  basilar  artery.  Its  posterior  surface  is  concave 
and  forms  the  upper  part  of  the  floor  of  the  fourth  ventricle.  A 
coronal  section  will  divide  it  into  an  anterior  or  inferior  portion  and  a  posterior 
or  superior  portion.  The  posterior  part  is  called  tegmentum.  The  anterior 
part  consists  of  three  main  divisions  (1)  superficial  transverse  fibres  which  pass 
from  the  middle  peduncles  of  the  cerebrum  and  give  the  pons  its  name.,  (2) 
deep  transverse  fibres  which  decussate  in  the  pons  connecting  one  side  of  the 
cerebellum  with  the  opposite  side  of  the  cerebrum.  (3) is  longitudinal  fibres  which 
intermingle  with  the  deep  transverse  fibres  and  pass  through  the  medulla  into 

PLATE  CLXXXIH. 


Location  of  Centers  of  the  Brain. 


the  crust  a  or  pes  of  the  crus.  The  tegmental  portion  of  the  pons,  or  posteior 
part,  has  four  main  parts.  Anteriorly  (1)  the  fillet.  (2)  formatio  reticularis, 
(3)  posterior  longitudinal  bundle-,  and  (4)  superior  olivary  nucleus. 

A  hemorrhage  in  the  pons,  if  it  is  above  the  decussation  of  the  seventh  nerve 
will  cause  paralysis  of  the  opposite  side  of  the  face  and  opposite  side  of  the  body 
but  if  it  is  below  the  decussation  of  the  seventh  nerve  it  will  cause  paralysis  of 
the  same  side  of  the  face  and  opposite  side  of  the  body,  producing  what  is  known 
as  crossed  hemisphlegia.  The  sixth  nerve,  seventh  nerve,  and  par'  of  the 
eighth  nerve  have  their  deep  origin  in  this  part  of  the  pons.  The  crus  cerebri 
or  the  peduncles  of  the  cerebrum  pass  upward  and  outward  from  the  upper 
margin  of  the  pons  into  the  substance  of  the  cerebrum.  They  are  about  three- 
fourths  of  an  inch  long.  A  cononal  section  will  divide  this  into  an  anterior  or 
inferior  and  a  posterior  or  tegmental   portion.     The  anterior  is  called  crusta 


364 


ANATOMY    IN    A    NUTSHELL. 


or  pes  and  has  motor  fibres  in  it.     The  posterior  portion  is  the  tegmental  por- 
tion and  has  sensory  fibres  in  it. 

The  Restiform  body  or  inferior  peduncles  of  the  cerebellum  receives  its 
fibres  from  four  main  sources  (1)  from  the  nucleus  gracilis  et  cuneatus  of  the 
same  side.  (2)  from  nucleus  gracilis  et  cuneatus  of  opposite  side,  (3)  from  the 
lateral  column  of  the  cord  through  the  direct  cerebellar  tract,  (4)  from  the 
nucleus  of  the  olivary  body  of  the  opposite  side. 

PLATE  CLXXXIV. 


A  Sagittal  Section  ok  the  Brain. 

The  area  where  the  cranial  nerves  leave  the  brain  substance  is  called  the 
Si  perficial  ORIGIN.  The  group  of  cells  from  which  the  fibers  spring  or  in  which 
they  end  is  the  deep  origin.     (Plate  CLXXXVII). 

Rule. — The  deep  origin  of  all  the  cranial  nerves,  except  the  first  and  sec- 
ond ;ind  a  part  of  the  eleventh,  is  in  the  floor  of  the  aqueduct  of  Sylvius  or 
in  the  floor  of  the  fourth  ventriclk.  The  third  and  fourth  have  their  deep 
origin  in  the  aqueduct  of  Sylvius.  The  fifth,  sixth,  seventh,  eighth,  ninth, 
tenth,  pari  of  the  eleveth,  and  twelfth  have  their  deep  origin  in  the  floor  of  the 
fourth  ventricle.  • 

Definition  for  centre. — (1)  Any  ganglion  or  plexus  giving  off  nerves 
which  control  function.  (2)  Any  GROUP  of  ganglion  tells  which  has  a  stim- 
ulating or  inhibitory  office.  (3)  It  is  a  group  of  GANGLION  CELLS  closely  con- 
nected with  one  another  and  acting  together  in  the  performance  of  some  func- 
tion, as  the  cerebral  centers,  psychical  centers;  respiratory  or  vaso-rnotor  cen- 
ter-. 

The  first  and  second  cranial  nerves  are  processes  of  the  brain  and  therefore 
have  neither  superficial  nor  deep  origin.  We  say  there  are  twelve  pairs  of 
cranial  nerves;  it  would  be  better  to  say  twelve  sets  for  in  the  first  or  olfactory 
nerves  there  are  twenty  or  thirty  nerves.  The  first  nerve  is  one  of  special  sense, 
thai  of  smell.     The   primary   center   for  smell  is  in  the  olfactory  lobe.      (Plate 


ANATOMY    IN    A    NUTSHELL. 


365 


CXCIX)    the    secondary   center  in  the  uncinate  gyrus  of  the    temporal    lobe 

on  the  mesial  surface.  (Plate  CLXXXII).  This  has  been  demonstrated 
by  experiments  upon  animals  and  by  pathological  research  on  the  brain  of  man. 
In  osmatic  animals  these  lobes  (gyrus  hypoeampus,  uncinate,  and  hippocampus 
major)  where  the  center  of  smell  is  located,  are  well  defined.  In  anosmatic 
they  aresmall.  If  the  olfactory  tract  be  removed  these  lobes  will  atrophy  and  in 
case  of  lesion  in  these  lobes  the  loss  of  smell  (anosmia)  will  follow.  The  ol- 
factory tracts,  which  are  white,  lie  almost  parallel  to  one  another,  extending 
from  the  under  surface  of  the  frontal  lobe.  The  bulb  is  reddish-gray  in  color 
and  lies  on  the  cribriform  plate  of  the  ethmoid.  From  the  bottom  of  these  bulbs  the 
olfactory  nerves  are  given  off,  twenty  or  thirty  in  number,  to  be  distributed  to 
the  cells  of  Schultze  in  the  Schneiderian  membraxk.  The  three  roots 
from  the  tracts  are  the  external,  middle,  and  internal.     The  external  root 

PLATE  CLXXXV. 


Showing  Long  and  Short  Association  Fibers  of  the   Brain. 

is  white  and  extends  into  the  anterior  end  of  the  hippocampus  gyrus  of  the  tem- 
poro-sphenoidal  lobe.  The  middle  one  is  gray  and  ends  in  the  trigonum  ol- 
factorium.  The  inner  one,  or  mesial  hoot,  is  white  and  passes  backward  and 
inward  to  end  in  the  anterior  extremity  of  the  gyrus  fornicatus.  The  mesial 
root  is  continuous  with  one  end  of  the  limbic  lobe  and  the  external  root  with 
the  other.  This  nerve  is  made  up  exclusively  of  non-medullated  fibers.  They 
are  deficient  in  the  white  substance  of  S<  hwann  and  consist  of  axis-cylinders  with 
a  distant  nucleated  sheath  in  which  there  are,  however,  fewer  nuclei  than  in  the 
ordinary  non-medullated  fibers. 

1.  Anosmia  is  the  loss  of  smell. 

2.  Hyperosmia  is   increased  sensitiveness. 

3.  Parosmia  is  perversion  of  the  Function  of  smell. 

4.  Kakosmia  is  a  condition  where  everything  smells  alike  to  the  patient  and 
the  odor  is  a  peculiar  or  offensive  one. 


366 


ANATOMY   IN    A    NUTSHELL. 


The  arachnoid  holds  the  tracts  in  position  in  the  sulci.  The  dura  mater 
covers  the  nerves  and  is  continuous  with  the  periosteum  of  the  nasal  fossa.  The 
pia  mater  is  continuous  with  the  neurilemma. 

PLATE  CLXXXYI. 


CuHNU  OF  LE.-T   LATERAL  VENTRICLE 


ANTERIOR  PILLAR  OF  FORNIX 


ROSTRUM  OF  CORPUS  CALLOSUM 

TENIA  SEMICIRCULARIS 

EXTERNAL  CAPSULE 

CLAUSTRUM 


PIA  MATER 
IN  HIPPOCAMPAL  FISSURE 


OF  CORPUS  CALLOSUM 
POSTERIOR  CORNU  OF  LEFT  LATERAL  VENTRICLE 

A  Horizontal  Section  (5fthe  Brain. 

The  second  cranial  nerve  or  optic  nerve  is  a  process  of  the  brain  like  the 
olfactory.  The  center  for  sigh*  bin  the  cuneate  lobule  of  the  occipital  lobe.  The 
optic  aerve  extend-  forward  and  outward  from  the  optic  commissure  or  chiasma 
to  the  posterior  part  of  the  eye-ball,entering  a  little  to  the  inner  side  of  the  cen- 
ter to  spread  out  into  the  retina.  The  chiasma  or  commissure  is  rectangular  and 
upon  the  olivary  eminence  of  the  sphenoid  bone  and  on  the  anterior  part 


ANATOMY  IN  A  NUTSHELL 


367 


of  the  diaphragma  sella.  Above  it  is  the  lamina  cinerea,  behind  it  is  the 
tuber  cinereum.  On  either  side  is  the  anterior  perforated  space.  The  optic 
tracts  extend  outward  and  backward  from  the  chiasma  to  (1)  the  external  gen- 
iculate  body.     (2)  The    posterior   or   inferior    quadiigeminal   body.     (3)  The 

PLATE  CLXXXVII. 


DESCUSSATION  OF  PYRAMIDS. 

Showing  Superficial  Origin  of  the  Cranial  Nerves. 

internal  geniculate  body.  (4)  Under  part  of  the  pulvinar  of  the  optic  thala- 
mus. From  these  four  parts  the  optic  radiations  extend  to  the  center  of  sight. 
Those  fibers  which  do  not  decussate  at  the  OPTIC  COMMISSURE  have  already 
decussated  in  the  corpora  quadrigemina.  This  is  the  reason  that  a  lesion  of 
one  center  of  sight  will  cause  blindness  in  the  opposite  eye  and  vice  versa,  for 
both  sets  of  decussating  fibers  are  destroyed.      A  lesion  through  the  middle  of 


368 


ANATOMY    IN    A    NUTSHELL. 


the  chiasms  will  produce  blindness  in  the  inner  half  of  each  eye.  A  lesion  of 
the  left  optic  nerve  will  produce  blindness  in  the  left  eye  and  vice  versa.  A 
lesion  of  the  left  optic  tract  will  produce  blindness  in  the  left  half  of  each  eye 
and  vice  versa.  As  this  nerve  pass<  s  from  the  brain  it  receives  coverings  from 
the  dura  mater, arachnoid, and  pia  mater.  It  passes  through  the  optic  foramen 
with  the  ophthalmic  artery,  being  above  and  on  the  inner  side  of  the  artery. 
The  optic,  motor  oculi,  trochlear,  trifacial,  and  the  abducent  nerves 
are  all  concerned  with  the  eye -ball  and  its  apparatus,  thus  making  all  the  of 

PLATE  CLXXXVIII. 


INTERNAL      GCNICULATE     BODY 
4TH  CRANIAL  N 

SUPERIOR  PEDUNCLE 


MEUDLLART   VELUM 


great  horizontal  fissure. 
Tim:  Superior  View  of  the  Cerebellum. 

first  six  cranial  nerves,  excepting  the  first.  The  optic  nerve  is  the  nerve  of  sight. 
The  motor  oculi,  trochlear,  and  abducent  are  th<  nerves  to  the  mnscles  of  the 
eyeball,  and  the  fifth  nerve  supplies  the  ophthalmic,  lenticular,  or  ciliary  gang- 
lion with  one  of  iis  roots,  from  which  ganglion  nerves  pass  to  the  iris. 

The  eyeball  is  Located  in  the  orbit  which  consists  of  seven  bones,  viz.,  (1) 
frontal,  (2)  ethmoid,  (3)  sphenoid,  (4)  lachrymal,  (5)  superior  maxillary,  (6) 
malar,  and  (7)  palate.  In  the  two  orbits  there  arc  but  eleven  bones,  the  frontal, 
ethmoid  and  sphenoid  being  common  to  the  two.  The  orbit  is  somewhat 
pyramidal  in  shape  with  the  base  forward  and  apex  backward.  (Plate  CCXXIX 
The  axial   lines,  if  extended,  would   meei  on  the  sella  turcica  of  the  sphenoid. 


ANATOMY    IN    A    NUTSHELL. 


369 


The  orbit  communicates  with  the  cavity  of  the  cranium  by  (1)  the  optic  fora- 
men and  (2)  the  sphenoidal  fissure.  It  communicates  with  four  fossa?,  (1)  with 
the  nasal  fossa  by  the  nasal  duct.  (2)  with  the  temporal  fossa,  (3)  with  the 
zygomatic  fossa.  (4)  and  with  the  spheno-maxillary  fossa.  These  last  three  by 
the  spheno-maxillary  fissure. 

Each  orbit  has  nine  foramina. — (1)  supraorbital,  (2)  infraorbital.  (3)  an- 
terior ethmoidal,  (4)  posterior  ethmoidal.  (5)  optic.  (6)  sphenoidal  fissure,  (7) 
spheno-maxillary  fissure.  (8)  nasal  duct,  (9)  malar  foramina. 

LESSON  CV. 

The  floor  is  formed  by  three  bones,  (1)  the  orbital  surface  of  the  superior 
maxillary;  (2)    the  orbital  process  of  the  malar;    (3)  the   orbital  process  of  the 

PLATE  CLXXXIX. 


CPTIC  TRACT 
3RD  CRANIAL  N. 
EXTERNAL  GENICULATE  BODY.  . 
MIDDLE  PEDUNCLE 


-OPTIC  TRACT. 
4TH  CRANIAL  NERVE. 
-EXTERNAL  GENICULATE  BODY. 

MOTOR  RCOT  OF  bTH  N. 
SENSORY  RCOT  OF  5TH  N. 


"GREAT  HORIZONTAL  FISSURE' 

The  Inferioe  View  of  the  Cerebellum. 

palate.  The  floor  is  somewhat  fiat  and  has  (1)  the  infraorbital  canal;  (2)  a 
depression  for  the  Inferior  oblique  muscle  anteriorly;  (•">)  the  infraorbital  groove 
posteriorly;  (4)  the  palato-maxillary  suture  posteriorly.  The  root'  is  formed 
by  the  two  bones.  (1)  the  orbital  plate  of  the  frontal  bone  anterior- 
ly; (2)  the  lesser  wing  of  the  sphenoid  posteriorly.  The  ROOF  is  dome-like. 
At  its  outer  angle  is  the  lachrymal  fossa  for  the  lachyrmal  gland.  The  depr<  ssion 
for  theSuperior  oblique  muscle  is  at  the  inner  angl<  .  Tin  inner  wall  is  formed 
by  four  bom  s,  (1)  the  nasal  proc<  ss  of  the  superior  maxillary ;  (2)  the  lachrymal 
bone;  (3)  the  os  planum  of  the  ethmoid;  (4)  body  of  the  sphenoid. 

It  has,(l)  lachrymal  crest;(2)  groove  for  lachrymal  sac;  (3)  ethmo-lachry- 
mal  suture;  (4)  ethmo-sphenoidal  foramina. 


370 


ANATOMY    IN    A    NUTSHELL 


The  outer  wall  is  formed  by  two  bones,  the  orbital  process  of  the  malar  and 
the  greater  wing  of  the  sphenoid  bone.  It  presents  (1)  the  opening  of  the  malar 
canal.  (2)  spheno-malar  suture.  The  four  boundaries  of  the  orbit  make  four 
angles,  viz.,  the  stjperiob  external,  superior  internal,  inferior  external, 
and  inferior  internal.   The  superior  external  angle  has(l)  fronto-malar  and 

PLATE  CXC. 


Showing  the  Writing  Center  in  the  Brain. 

fronto-sphenoidal  articulation,  (2)  the  sphenoidal   fissure  which  transmits  the 
third,  fourth,  three  divisions  of  the  ophthalmic  division  of  the  fifth, and  sixth 
nerves,   filaments  of  the  sympathetic,  processes  of  the  dura  mater,  orbital 
branches  of  the  middle  meningeal  and  recurrent  lachrymal  arteries. 


PLATE  CXCI 


CONUS     MEDULLARS 


GANGLION  ON  A  POSTERIOR     NERVE     ROOT 


ANTERIOR      SPINAL  ARTERY 


-THORACIC  XII 


LUMBAR  I 


COCCYGEAL 
FILUM     TERMINALE  SURROUNDED    BY     CANDA    EQUINA 


Antkkiok  Yikw  of  Cauda  Equin  \. 
371 


372 


ANATOMY    IN    A    NUTSHELL. 


The  superior  internal  angle  has  (1)  the  lachrymo-ethmo-frontal  suture, 
anterior  ethmoidal  foramen  which  transmits  the  anterior  ethmoidal  vessels,  and 
nasal  nerve,  (2)  the  posterior  ethmoidal  foramen  which  transmits  the  posterior 
ethmoidal  vessels  and  sometimes  a  branch  of  the  nasal  nerve.  The  inferior  ex- 
ternal angle  has  the  spheno-maxillary  fissure  which  is  formed  by  the  greater 
wing  of  thf  sphenoid  bone  externally  and  the  superior  maxillary  bone  and  palate 
bone  internally.  This  fissure  connects  the  orbit  with  (1)  the  temporal  fossa, 
(2)  zygomatic  fossa,  (3)  spheno-maxillary  fossa  and  transmits  the  infraorbital 
artery,  superior  maxillary  nerve  and  its  orbital  branches    and    the    ascending 

PLATE  CXCII. 


LIGAMENTUM       DENTICULATUM 


POSTERIOR  ROOT 


LINEA 
SPLENDNS 

ANTERIOR    ROOT 

Showing  the  Dura  Mater,  Arachnoid,  and  Piamater. 

branches  of  Meckel's  ganglion.  The  inferior  internal  angle  has  the  ethmo-max- 
illo-palato-lachryma]  suture.  At  the  apex  of  the  orbit  is  the  optic  foramen 
which  is  between  the  two  roots  of  tin  h  sser  wing  of  the  sphenoid.  It  transmits 
the  optic  nerve  and  opthalmic  artery,  the  nerve  lying  above  and  inner  to  the 
arten-.  The  ligament  of  Zinn  is  attached  to  the  circumference  of  the  optic 
foramen, deficient  at  the  upper  and  outer  part, and  gives  a  common  origin  to  the 
four  Recti  OlUSCleS.  The  supraorbital  notch  or  foramen  is  situated  at  the 
junction  of  the  inner  and  middle  third  of  the  upper  circumference  of  the  orbit. 
It  transmits  the  supraorbital  vessels  and  nerve.  A  line  drawn  from  this  notch 
or  foramen  In  the  mental  foramen  passes  through  the  infraorbital  foramen. 
There  are  EIGHT  MUSCLES  in  the  orbit,  viz..  the  four  Recti,  the  two  Oblique, 


ANATOMY    IX    A    NUTSHELL. 


373 


Levator  palpebrae,  and  the  Tensor  tarsi  (Horner's  muscle). 

1.  Papillitis  is  an  inflammation  of  the  optic  papilla. 

2.  Xeuroretinitis  is  inflammation  of  the  optic  nerve  and  retina. 

3.  Retrobulbar   Neuritis  is  an  inflammation  behind  the  eye-ball. 

PLATE  CXCIII. 

POSTER  0- MEDIAN  SlUXUS 

H 

r^C\      A.      ATTHELEVEL   OF  THE6TH  CERVIC/-.  NERV-  fi00rr 
ANTERIOR  FISSURE 


CENTRAL  CANAL 


B.AT  THE  MID- DORSAL  REGION 


POSTERIOR  ROOTS 


ANTERIOR  ROOTS 


CAT  THE  CENTRE  OF  THE  LUMBAR  ENLARGEMENT 


0.    AT  THE  UPPER  PART   OF  THE  CONUc  MEDULLARS 


E.  AT  THE  LEVEL  OF  THE  5TH  SACRAL  NERVE    ROCTi 


L  AT  THE  LEVEL  OF  THE    COCCYGEAL  NERVE  ROOTS 

Transverse  Sections  <>k  the  Cord  at  Different  Li.\  els. 

4.  Amblyopia  is  a  dimness  of  vision  from  imperfect  sensation  of  the  re- 
tina and  without  an  organic  lesion  of  the  eye, 

5.  Amaurosis  is  blindness,  especially  blindness  occuring  without  apparent 
lesion  of  the  eve.  from  disease  of  the  optic  nerve,  retina,  spine  or  brain. 


374 


ANATOMY    IN    A    NUTSHELL. 


6.  Retinal  or  oculae  hyperesthesia  is  a  condition  in  which  the  eye  is 
abnormally  sensitive  to  light. 

7.  Ny<  i  ai.< h'Ia  is  a  condition  where  the  patient  can  see  better  in  dim  light. 

8.  Hemianopsia  is  half  blindness,  a  condition  in  which  there  is  blindness 
of  one-half  of  the  visual  held. 

9.  Myopia  is  short-sightedness,  too  great  refracting  power  of  the  eyes  so 
lhat  the  rays  coining  from  an  object  beyond  a  certain  distance  are  fixed  in  front 
of  the  retina. 

PLATE  CXCIV. 


MARGINAL  ZONE  OR  LISSAUER  S  TRACT. 

A  Transverse  Section  of  the  Cord,  Showing  Tracts,  Diseases,  Etc. 

10.  Hypermetropia  or  hyperopia  is  far-sightedness,  the  focusing  of 
parellel  rays  behind  the  retina. 

11.  Presbyopia  is  long-sightedness,  an  impairment  of  vision  due  to  old 
age  dependenl  upon  diminution  of  the  power  of  accommodation  from  loss  of 
elasticity  of  the  crystalline  lens,  causing  the  near-point  of  distinct  vision  to  be 
removed  farther  from  the  eye. 

12.  Emmetropia  is  a  normal  condition  of  the  eye  as  respects  refraction. 

13.  Astigmatism  is  a  condition  caused  by  inequality  of  the  curvature  of 
the  different  meridians  of  the  cornea.  Itmaybe  caused  by(l)  imperfections  of 
the  lens,  (2)  unequal  contraction  of  the  ciliary  muscles,  (3)  retinal  imperfections. 


PLATE  CXCV 


PARUTiD  GUND 
TEMPORAL 
'DISTRIBUTION  OF  FACIAL  NERVE 


POSTERIOR  AURICULAR  A. 


SUBMAXILLARY  GLAND 


EXTERNAL      CAROTID 


SUBCLAVIAN  ARTERY 


VEIN 

INTERCOSTAL  ARTERY 

NERVE 


THE    SYMPATHETIC  GANGLIA 


COELIAC     AXIS 


$1     *.  ' •* fig  *J*Sfe<i   i  '  ^ 


INNOMINATE     ARTERY 

PARVAGUM    OR 
PNEUMGGASTRIC 


Jjx.  V  -  — =^S*^SUP    VEJENTERiC 

"V^).',  \^^^T        VSLiP   MESEV 


SPLENIC     ARTERY 
WITH     SPLENIC      PLEXUS 


ARTERY   WITH 
ESENTERIC  PLEXUS 


RIGHT  COMMON  CAROTID  ARTER 


SPERMATIC  CCRD 


IT?/'     '         '   - 

if- 


NFERIOR  MESENTERIC  ART 
ITH  INF    MES      PLEXUS 


PUBIS  SYMPHYSIS 


Vena  Azygos  Major,  Abdominal  Aorta  and  Sympathetic  Nerve. 

375 


370  ANATOMY   IN    A   NUTSHELL. 

There  are  seven  muscles  in  the  orbital  region,  viz.,  (1)  Levator  palpebrae 
superioris,  (2)  Rectus  superior,  (3)  Rectus  inferior,  (4)  Rectus  internal,  (5)  Rec- 
tus external,  (6)  Superior  oblique,  (7)  Inferior  oblique.  All  of  these  are  attach- 
ed to  the  eye-ball  except  the  Levator  palpebrae  superioris.  The  third  nerve  sup- 
plies five  of  these  seven  muscles,  ail  except  the  Superior  oblique  which  is  sup- 
plied by  the  fourth,  and  the  External  rectus  which  is  supplied  by  the  sixth. 
(Plate  CCVI). 

The  eye-ball  is  spheroidal  in  shape,  but  consists  of  the  segments  of  two  spheres, 
a  portion  of  the  smaller  sphere  forming  its  anterior  transparent  part,  and  being 
set  on  the  front  of  the  posterior  segment,  which  is  a  part  of  the  larger  sphere. 

The  eye-ball  consists  of  three  coats,  sclerotic,  choroid,  and  retina. 

(a)  The  sclerotic  coat  is  an  opaque,  white,  dense,  fibrous,  inelastic  mem- 
brane,  continuous  with  the  cornea  in  front,  the  two  forming  the  external  coat 
of  the  eye-ball. 

(b)  The  choroid  is  a  delicate,  highly  vascular  membrane,  forming  one  of 
the  coats  or  tunics  of  the  eye-ball,  lining  the  sclerotic,  and  lying  between  it  and 
the  retina,  with  which  it  is  in  contact  by  its  inner  surface. 

(c)  The  retina  is  the  innermost  and  chiefly  nervous  coat  of  the  posterior 
part  of  eyeball,between  the  choroid  coat  and  vitreous  humor.  It  may  be  divided 
into  ten  layers.     ( Plate  ('('). 

The  eye-ball  has  three  refracting  media,  the  aqueous  humor, the  crystalline 
lens,  the  vitreous  humor. 

(a)  The  aqueous  humor  is  a  limpid,  watery  fluid  which  fills  the  space  be- 
tween the  cornea  and  the  crystalline  lens  of  the  eye. 

(b)  The  crystalline  humor  or  lens  is  a  lentiform  pellucid  body,  com- 
posed of  transparent  firm  substance,  inclosed  in  a  membraneous  capsule  and 
situated  in  front  of  the  vitreous  humor  and  behind  the  iris  of  the  eye. 

(c)  The  vitreous  humor  is  a  pellucid  gelatine  substance  which  fills  about 
four-filths  of  the  hall  of  the  eve.  behind  the  crystalline  lens. 


LESSON  CVI. 

The  eye-ball  is  composed  of  three  investing  tunics  and  three  refracting 
media.  From  without  inward  the  tunics  are  (1)  fibrous,  consisting  of  (a)  scele- 
ROTIC  and  (b)  cornea;  (2)  Vascular  (tunica  vasculosa  oculi),  consisting  of  (a) 
choroid,  (b)  ciliary  body,  and  (c)  iris;  (d)  Nervous  coat  or  retina  consisting 
of:     (Plate  (V,. 

1.  Membrana  limitans  interna. 

'_'.    Fibrous  layer,  consisting  of  nerve-fibres. 

:;.   Ganglionic  layer,  consisting  of  nerve-cells. 

\.    Inner  molecular,  or  granular,  layer. 

5.  Inner  nuclear  Layer, 

6.  Outer  molecular,  or  granular,  layer. 

7.  ( )uter  nuclear  layer. 

8.  Membrana  limitans  externa. 

9.  Layer  of  roils  and  cones  (Jacob's  membrane). 


PLATE  CXCVI. 


ANTERIOR     VIEW     0^     PONS     VAROLII 


Trt.utMINUS  NERVE     (DlV'r..) 


7«ttfc 


GLOSSOPHARYNGEAL 
VAGUS  AND  SPINAL  ACCESSORi 


HYPOGLOSSAL  NERVE 

iUALENUS  ANTICUS 

SUBCLaKIAN  ARTERY 
FIRST  RIB 


p  ifel1  ■  14*- 


INTERNAL  CA"CTIO 

"    INTERNAL  JUGULAR     V£|N 
'.  EDULLA       OBLONGATA 


"  .7ERI0R  CERVICAL  GAN:LION 
STERNO-CLEIDO  MASTOID 


ism , 


MIDDLE  LcHVICH  GANGLION 


BRACHIAL     PLEXUS 


INFERIOR  CERVICAL  G  '  SGLION 


INTERCOSTAL      ARTE    I 

—  VEIN 

NERVE 


SYMPATHETIC  GANGLIA 


OUADRAIUS  LUMBORUM 


:-§mm 


Tv)  « 


LIO-HYPOGASTRIC  N 


LIO- INGUINAL  N. 


EXTERNAL  CUTANEOUS 


GENITO  CRURAL 


SACRAL  GANGI  IA 


OR  CRURAL  NERVE 


my$r 

v    r     v  ^  GRE4T  SCIATIC 

rnrrv» 

Anterior  View  of  Sympathetic  Nerve  and  Spinal  Cord 

377 


OBTURATOR  N 


378  ANATOMY    IN    A    NUTSHELL. 

10.  Pigmentary  Layer. 

The  refracting  media  are  (1)  Aqueous  humor,  (2)  Vitreous  humor,  and 
(3)  Crystalline  lens. 

The  capsule  of  Tenon  is  a  layer  of  fascia  which  surrounds  the  posterior 
five-sixths  of  the  eve-hall.  Where  the  optic  nerve  enters  it  is  continuous  with 
the  sclerotic  coat.  Anterior  it  is  connected  loosely  to  the  sclerotic  at  the 
corneo-sclerotic  junction.  It  is  pierced  by  the  tendons  of  the  four  Recti  and 
two  Oblique  muscles  of  the  eye.  Between  the  anterior  and  posterior  attach- 
ments there  is  a  delicate  attachment,  between  the  capsule  and  the  eye-ball, of 
connective  tissue;  these  constitute  extensively  lymphatic  spaces  in  which  the 
eve-ball  glidesjthis  is  a  ball-and-socket  (enarthrodial)  joint.  An  expansion  from 
the  sheath  of  the  Superior  oblique  muscle  blends  with  the  tendon  of  the  Levator 
palpebrse.  An  expansion  from  the  Inferior  rectus  is  attached  to  the  inferior 
tarsal  plate,  therefore  these  two  Recti  muscles  influence  the  movements  of  the 
evelids.  The  expansion  of  the  sheath  of  the  Internal  rectus  is  attached  to  the 
lachrymal  bone  and  is  called  the  internal  check  ligament.  The  expansion  from 
the  External  retcus  which  is  very  strong,  is  attached  to  the  malar  bone  and  is 
called  the  external  check  ligament.  The  suspensory  ligament  of  the  eye  is  at- 
tached to  the  malar  and  lachrymal  bones,  passing  below  the  eye-ball  ;it  is  narrow 
at  each  extremity  and  broad  in  the  center.  The  anterior  pole  is  the  central 
point  of  the  anterior  curvature  of  the  eye-ball  ;the  posterior  pole  is  the  central 
point  of  the  posterior  curvature.  The  sagittal  axis  is  a  line  joining  these  two 
poles.  The  transverse  diameter  of  the  eyeball  is  about  one  inch,  the  verti- 
cal nine-tenths,  and  the  antero-posterior  is  intermediate. 

The  sclerotic  coat  is  fibrous  and  opaque  tunic, occupying  the  posterior  five- 
sixths  of  the  eye-ball.  It  is  continuous  in  front  with  the  cornea.  The  outer 
surface  is  white,  being  covered  with  conjunctiva.  It  is  smooth,  except  where 
the  muscles  are  inserted.  Its  inner  surface  is  brown  and  marked  by  grooves 
for  the  ciliary  vessels  and  nerves  and  is  loosely  connected  to  the  outer  surface 
of  the  choroid  by  fine  cellular  tissue  (lamina  fusca)  thus  forming  the  perichoroi- 
deal  lymphatic  spaces.  The  optic  nerve  passes  through  the  posterior  part  of 
the  sclerotic  coat  about  one-eighth  of  an  inch  internal  to  the  axis  of  the  eye-ball. 

The  point  of  perforation  is  called  the  lamina  cribrosa.  The  outer  sheath  of 
the  optic  nerve  blends  with  the  sclerotic  coat  at  its  entrance.  The  sclerotic  is 
thickest  at  the  posterior  part  of  and  thinnest  about  one-fourth  an  inch  from  the 
cornea.  The  canal  of  Schlemm,  or  sinus  venosus  scleroe,  is  close  to  the  junction 
of  the  cornea  with  the  sclerotic;  ii  is  a  snail  circumferential  lymphatic  space. 
The  structure  of  the  sclerotic  is  white  fibrous  tissue  intermingled  with  elastic 
tissue  and  flattened  connective  tissue  corpuscles  which  are  contained  in  the  cell 
between  the  fibers.     Some  of  the  corpuscles  are  pigmented. 

The  nerves  are  from  the  ciliary,  but  their  mode  of  ending  is  not  known. 
The  vessels  are  from  the  short  and  anterior  ciliary  arteries  of  the  ophthalmic. 

The  cornea  is  transparent  and  forms  about  one-sixth  of  the  circumference 
of  the  eye-ball  anteriorly.  It  is  a  segment  of  a  smaller  sphere  than  that  which 
forms  the  posterior  five-sixths.  It  fits  into  the  sclerotic  coat  somewhat  like 
a  watch  crystal  fits  into  the  face  of  a  watch,  thus  projecting  beyond  the  curva- 


PLATECXCVII. 


GANGLION  OF  RIBES 


70  GANGLION  OF  ROOT  OF  PNEUMOGASTRIC 

TO  PETROUS  GANGLION  OF  GLOSSO:PHAR 
1ST.  CERVICAL  NERVE 
-<ND 


CAROTID  PLEXUS 

TO  5TH.  NERVE 

^~-  TO  4TH.  NERVE 
CAVERNOUS  PLEXUS  ,  LARGE  SUPERFICIAL     PETROSAL 

VIDIAN —  TO-MECKEL  S— GANGLION 
'LARGE  DEEP  PETROSAL 


TO-BRANCHES    OF    EXTERNAL    CAROTID    ARTERY 


<■+  CARDIAC     BRANCHES      FROM    PNEUMOGASTRIC 

*%      S^,    V     \        I  AND     RECURRENT    LARYNGEAL  NERVES 

GANGLION    OF     WRISBERG 


HEPATIC    PLEXUS 

CYSTIC    PLEXUS 

GASTRO  DUODENAL     PLEXUS 

PYLORIC   PLEXUS 
GASTRICV  PLEXUS 


ST    SACRAL    NERVE^T  — < 


5TH.    SACRAL       NERVE 


^PELVIC-  OR     INFERIOR      HYPOGASTRIC    PLEXUS 


GANGLION     OF     IMPAR 


CUUCYGEAL    NERVE 

A  Side  View  of  Sympathetic  System. 
379 


380 


ANATOMY    IX    A   NUTSHELL. 


ture  of  the  sclerotic.  It  is  continuous  with  the  sclerotic  coat.  The  posterior 
surface  o(  the  cornea  is  concave  and  projects  a  little  farther  backward  than  the 
anterior  convex  surface.  The  posterior  surface  of  the  cornea  forms  the  anterior 
boundary  of  the  anterior  chamber  which  contains  aqueous  humor.  Its  anterior 
surface  is  covered  with  conjunctiva  which,  in  this  position,  constitutes  one  of 
the  epithelial  layers.  It  is  of  a  uniform  thickness  and  is  more  curved  in  youth 
than  in  old  age,  when  it  becomes  flattened. 

The  ligamentum  pectinatum  iridis  or  the  pillars  of  the  iris,  are  formed  by 
fibers  from  the  stroma  of  the  cornea  which  pass  backward  and  outward  to  the 
iris.     They  form  an  annular  meshwork  encircling  a  series  of  lymphatic  spaces 


PLATE  CXCVIII. 


,-  FROM  RAMUS  COMMUNICANS 
|     TO  VERTEBRAE  AND  INTERCOSTAL 
AND  LUMBAR  VESSELS 


TO     HIGHER     GANGLION 
0.', 


SOMATIC  VASOMOTOR,    PILOMOTOR,    SECRETORY 
H 


SYMPATHETIC  TRUNK 


MEDULLATED     FIBERS    PASSING 

a    THROUGH  THE  GANGLION    TO 

PREVERTEBRAL  PLEXUS  OR 

DIRECTLY  TO  VISCERA 

*    GRAY  VISCERAL  FIBERS 


RAMI EFFERENTES 


SYMPATHETIC  TRUNK 


vertebrae 

ligaments 
spinal  vessels 
and   Dura 


NTRAL  SPINAL  NERVE  ROOT 


DORSAL  SPINAL  NERVE  ROOT 


ACCOMPANYING  DORSAL  ROOT  TO  DURA 

Showing  the  Rami  Communicantes. 

(spaces  of  Fontana)  which  communicate  with  the  anterior  chamber,  and  the 
canal  of  Schlemn,  and  the  scleral  veins. 

Structure. — The  cornea  consists  of  four  layers,  viz:  (1)  Several  strata 
of  epithelial  cells  continuous  with  those  of  the  conjunctiva,  (a)  The  external 
set  consists  of  columnar  epithelium,  (b)  Two  or  three  layers  of  polyhedral 
cells,  (c)  Three  or  tour  layers  of  scaly  epithelial  with  flattened  nuclei.  (2)  A 
(hick,  central,  fibrous  structure  called  the  substance  propria.  It  is  fibrous, 
tough,  unyielding,  perfectly  transparent  and  continuous  with  the  sclerotic  and 
consists  of  aliout  sixty  flattened  lamellae,  the  fibres  passing  one  lamella  to  an- 
other.    The  corneal  spaces  are  between  the  hunelhe,  which  are  connected  by  an 


ANATOMY    IN    A    NUTSHELL. 


381 


interstitial  cement  substance  and  each  space  contains  cells, the  conical  corpuscles 
which  are  stellate  in  shape.  (3)  A  homogenous  elastic  lamina.  (4)  A  single 
layer  of  endothelial  cells  forming  part  of  the  lining  membrane  of  the  anterior 
chamber  of  the  eye-ball. 

Besides  these  four  strata  we  have  the  anterior  and  posterior  elastic 
lamina.  The  anterior  clastic  lamina  (n  embrane  of  Bowman)  is  the  uppermost 
layer  of  the  corneal  stroma  immediately  beneath  the  conjunctival  epithelium. 
The  posterior  elastic  lamina  (membrane  of  Descemet  or  Demours)  is  the  pos- 
terior lining  membrane  of  the  cornea.  Its  function  is  to  preserve  the  correct 
curvature  of  the  cornea  proper.  The  nerves  are  numerous  and  are  derived  from 
the  ciliary.     It  is  non-vascular. 


LESSON  CVII. 

The  choroid  consists  of  two  layers, an  outer  and  an  inner.  The  inner  layer 
or  tunica  Ruyschiana  is  formed  by  the  capillary  endings  of  the  vessels  of  the 
outer  coat.     They  pass  forward  to  within  one-eighth  of  an  inch  of  the  cornea 

PLATE  CXIX. 


EXTERNAL  ROOT  FROM  TEMPORAL    LOE 


INTERNAL  ROOT  FROM  GYRUS  FORNICATUS. 


The  Olfactory  ok  First  Cranial  Nerve. 

joining  those  of  the  ciliary  processes.  The  choroid  consists  of  blood  vessels 
Connected  together  by  loose  connective  tissue  and  containing  large  branched 
and  pigmented  cells.  Externally  it  is  connected  to  the  selenitic  by  loose  con- 
i:<  ctive  t issue  forming  lymphatic  spaces.  It  is  a  continuation  of  the  pigmentary 
feells  of  the  retina.  The  choroid  is  thickest  behind  where  it  is  pierced  by  the 
optic  nerve.  The  outer  layer  contains  the  larger  branches  of  the  vessles.  The 
Bhoii  ciliary  arteries  after  piercing  the  sclerotic  close  to  the  optic  nerve  pass 
forward  and  inward  to  <  nd  in  the  inner  lay<  r  of  the  choroid.  The  venae  vorti- 
B<  -;r.  which  are  four  or  five  in  number,  are  formed  by  numerous  smaller  veins 
and  lie  external  to  the  arteri<  s.  They  pierce  th<  sclerotic  midway  be1  ween  the 
cornea  and  the  optic  nerve.  The  venae  vorticosae  form  the  two  ophthalmic 
veins  which  join  to  form  the  common  ophthalmic  v<  in.  The  common  ophthal- 
mic  vein  passes  from  the  orbit  through  the  internal  inferior  angle  of  the  sphen- 


382 


ANATOMY    IN    A   NUTSHELL. 


noidal  fissure  (anterior  lacerated)  into  the  cavernous  sinus  which  divides  into 
superior  and  inferior  petrosal  sinuses,  each  of  which  empties  into  the  lateral 
sinus.  The  lateral  sinus  and  inferior  petrosal  sinus  form  the  internal  jugular 
vein.  This  vein  receives  the  subclavian  vein  thus  forming  the  innominate  vein. 
The  two  innominate  veins  form  the  superior  vena  cava  which  empties  into  the 
righl  auricle  of  the  heart.    Thus  the  blood  passes  from  the  eye-ball  to  the  heart. 

PLATE  CC. 


PIGMENTARY  LAYER 


IAC0BS  MEMBRANE 


LAYER    OF    RODS  AND  CONES 


MEMBRANA     LIMITANS     EXTERNA   VIII 


OUTER  NUCLEAR     LAYEf 
OR  GRANULAR  LAYER 


OUTER    MOLECULAR    LAYER 


INNER    NUCLEAR    LAYER 
OR     GRANULAR  LAYER 


INNER  MOLECULAR  LAYER 


GANGLIONIC     LAYER 


OF  NERVE  CELLS 


LAYER  OF  NCf.VE  FIBERS 


p'lO 


CONE 


MEMBRANA   L'V.ITANS     INTERNA 


The  Layers  of  the  Retina. 

The  arterial  blood  passes  from  the  heart  to  the  eye-ball  as  follows: 
From  ili<'  lefl  ventricle  through  the  arch  of  the  aorta  through  which  it 
passes  in'"  the  common  carotid  on  the  right  side  it  must  first  go  through  the 
innominate  artery— from  the  common  carotid  into  the  internal  carotid  by 
means  of  which  it  which  passes  into  the  skull  through  the  carotid  canal  and' 
middle  lacerated  foramen.     Then  the  internal  carotid  gives  off  the  ophthalmic 


ANATOMY    IN    A    NUTSHELL 


383 


artery  which  passes  through  the  optic  foramen  into  the  orbit  with  the  optic 
nerve.  However,  this  artery  sometimes  passes  with  the  ophthalmic  vein  through 
the  anterior  lacerated  or  sphenoidal  fissure.  In  the  orbit  it  gives  off  the  fol- 
lowing branches,  an  orbital  group  and  an  ocular  group.  The  branches  of  the 
orbital  group  are: 

1.  Lachrymal.  2.  Supraorbital.  3.  Posterior  ethmoidal. 

4.  Anterior  ethmoidal.  5.  Internal  palpebral.  6.  Frontal 

7.  Nasal. 


PLATE  CCL 


CANAL  OF  SCHLEMM  AND  CONNEC- 
TIONS  WITH   ANTERIOR   CILIARY   VEIN 

BRANCH   FROW   CILIARY  BODY  TO 
ANTERIOR  CILIARY  VEIN 
VESSELS  OF  CILIARY    PROCESSES 

VEIN  FROM     IRIS    AND  CILIARY 
BODY   TO   VENA   VORTICO'SA 


foARGJNAL  CORNEAL  PLEXUS 

ANTERIOR  CONJUNCTIVAL  VEIN 


BRANCH    FROM    SHORT 
POSTERIOR  CILIARY  ARTERY 
TO  OPTIC   NERVE 


SHORT    POSTERIOR  CILIARY  ARTERY 
VENA  CENTRALIS  RETINAE 


CIRCULUS  IRIDIS    MAJOR 

CONIUNCTIVAL  VEIN 
ANTERIOR     CILIARY     ARTERY 
POSTERIOR   CONJUNCTIVAL  ARTERY 
ANTERIOR  CILIARY  VEIN 

EPISCLERAL  VEIN 
EPISCLERAL  ARTERY. 


VENA  VORTICOSA 


POSTERIOR  LONG  CILIARY    AflTERY. 
POSTERIOR     SHOT  CILIARY  ARTERIES. 

VESSELS  OF  PIAL    SHEATH  »F  OPTIC  HERVE 
VESSELS  CF  DURAL  SHEATH. 


wrteeia  centralis  retina. 
Blood  Supply  to  the  Eye-Ball.     (Leber). 


The  ocular  group  consists  of: 

1.  Short  ciliary  3.  Anterior  Ciliary. 

2.  Long  ciliary  4.  Arteria  centralis 
•I.  Muscular.  retinse. 

The  lachrymal  is  one  of  the  largest  branches  from  the  ophthalmic  ami 
comes  off  close  to  the  optic  foramen  although  it  may  come  off  before  the  artery 
passes  through  the  optic  foramen.  Occasionally  it  is  derived  from  one  of  the 
anterior  branches  of  the  middle  meningeal  artery.  It  passes  along  the  outer 
wall  of  the  orbit  above  the  External  rectus  muscle  with  the  Lachrymal  nerve. 
It  is  distributed  to  the  lachrymal  gland  and  to  the  eyelids  and  conjunctiva. 
Those  to  the  lids  are  two  in  number,  called  the  external  palpehral  running  in  the 


AXATOMY    IN    A    NUTSHELL. 


upper  and  lower  lids,  uniting  with  the  internal  palpebral.  It  gives  off  one  or 
two  malar  branches,  one  of  them  pass  through  the  malar  foramen  to  anasto- 
mose with  the  transverse  facial,  the  other  passes  through  a  foramen  in  the  malar 
bone  to  anastomose  with  the  deep  temporal  in  the  temporal  fossa.  A  branch 
from  the  lachrymal  passes  through  the  sphenoidal  fissure  to  the  dura  mater  to 
anastomose  with  the  middle  meningeal  artery.     (Plate  CCIII). 

The  supraorbital  artery  arises  above  the  optic  nerve  and  passes  above  the 

PLATE  CCII. 


CILIARY  ARTERY. 


LONG  POSTERIOR  CILIARY     ARTERY 

COPTIC    N. 

SHORT  POSTERIOR  CILIARY  ARTERIES       V 

V 

Showing  Vkn.k  Vorticose. 

muscles  and  b<  neath  the  root'  of  the  orbil  onto  the  forehead  through  the  supra- 
orbital foramen  with  the  supraorbital  nerve.  While  in  this  foramen  it  gives  off 
a  branch  to  the  diplce.  After  leaving  the  foramen  it  divides  into  superficial  and 
deep  branches.  It  supplies  muscles,  integument  and  the  pericranium  on  the 
forehead,  h  anastomoses  with  the  frontal,  anterior  temporal,  artery  of  the 
opposite  side,  and  angular  artery.  It  supplies  the  parts  at  the  inner  canthus. 
The  Superior  rectus  and  Levator  palpebral  are  supplied  by  it. 

The  posterior  ethmoidal  is  smaller  than  the  anterior  ethmoidal.      It  enters 
the  posterior  ethmoidal  foramen,  supplying  the  posterior  ethmoidal  cells,  giving 


ANATOMY    IX    A    NUTSHELL.  385 

off  a  branch  to  the  dura  mater  and  a  nasal  branch  which  passes  through  the  cribri- 
form plate  of  the  ethmoid  anastomosing  with  branches  of  the  spheno-palatine. 

The  anterior  ethmoidal  accompanies  the  nasal  nerve  through  the  anterior 
ethmoidal  foramen  into  the  cranium,  supplying  the  anterior  ethmoidal  cells  and 
frontal  sinus.  It  gives  meningeal  branches  to  the  dura  mater  and  passes  through 
the  nasal  slit  to  be  distributed  under  surface  of  the  nasal  bone  and  the  skin  of 
the  nose. 

The  internal  palpebral  are  two  in  number,  coming  from  the  ophthalmic 
opposite  the  pulley  of  the  Superior  oblique.  These  pass  between  the  dorsal 
cartilages  and  the  Orbicularis  palpebrarum. 

The  frontal  artery  is  one  of  the  terminal  branches.  It  passes  upward  at 
the  inner  angle  of  the  eye  anastomosing  with  the  supraorbital  and  the  artery  of 
the  opposite  side,  to  be  distributed  to  the  integument,  muscles,  and  pericranium. 

The  nasal  branch  is  another  terminal  branch.  It  leaves  the  orbit  above 
the  tendo  oculi.  It  gives  branches  to  the  lachrymal  sac.  Its  transverse  nasal 
branch  anastomoses  with  the  angular  and  its  dorsalis  nasi  supplies  the  outer 
surface  of  the  nose  and  anastomoses  with  the  artery  of  the  opposite  side  and 
lachrymal  branch  of  the  facial. 

The  ciliary  arteries  are  the  short,  long,  and  anterior.  The  short  ciliary 
are  eight  or  ten  in  number.  They  come  from  the  ophthalmic  or  some  of  its 
branches.  They  pierce  the  sclerotic  coat  forming  a  circle  around  the  optic 
nerve,  passing  forward  on  the  inner  surface  of  the  choroid,  supplying  the 
choroid  coat  and  the  ciliary  processes.  The  long  ciliary  are  two  in  number 
which  pierce  the  sclerotic  coat  running  forward  to  form  two  arches, the  circulus 
major  which  is  around  the  circumference  of  the  iris  and  the  circulus  minor 
around  the  papillary  margin.  The  anterior  ciliary  come  from  the  muscular 
branches  and  pass  forward  with  the  tendons  of  the  Recti  muscles.  They  form 
a  network  beneath  the  conjunctiva  and  pierce  the  sclerotic  coat  a  short  dis- 
tance from  the  cornea  to  join  the  circulus  major  at  the  iris. 

The  arteria  centralis  retina  pierces  the  optic  nerve  obliquely  about  one- 
fourth  an  inch  behind  the  eye-ball.  It  is  one  of  the  smallest  branches  of  the 
ophthalmic.  It  enters  the  globe  of  the  eve-ball  through  the  porus  opticus.  It 
supplies  the  inner  surface  of  the  retina  and  is  accompanied  by  the  corresponding 
veins.  In  the  fetus  a  branch  passes  from  this  artery  through  Stilling's  canal 
to  the  capsule  of  the  lens.     It  lies  beneath  the  sheath  before  it  pierces  the  nerve. 


LESSON   CVIII. 

Muscular  branches  are  given  off  from  various  branches  of  the  ophthalmic 
and  are  two  in  number,  the  superior  and  inferior.  They  may  come  from  Un- 
common trunk.  The  superior  one  supplies  the  Superior  rectus.  Levator  pal- 
pebrae,  and  Superior  oblique.  The  inferior  one  supplies  the  Inferior  rectus, 
External  rectus.  Internal  rectus,  and  Inferior  oblique.  This  inferior  one  gives 
off  one  of  the  anterior  ciliary  branches.  Muscular  branches  are  also  given  off 
from  the  lachrymal,  supraorbital,  and  the  ophthalmic  itself. 


386 


ANATOMY    IN    A   NUTSHELL. 


The  ciliary  body  consists  of  the  ciliary  processes  and  the  ciliary  muscle. 
The  ciliary  processes  are  of  the  same  structure  as  the  rest  of  the  choroid.  They 
are  a  series  of  folds  (seventy  or  eighty)  which  are  derived  from  the  anterior 
margin  of  the  choroid  and  are  received  in  the  corresponding  folds  of  the  sus- 
pensory  Ligament  of  the  lens  and  the  vitreous  humor.  The  blood  supply  is  the 
anterior  ciliary.  The  ciliary  muscle  consists  of  two  sets  of  involuntary  muscular 
fibers,  radiating  and  circular.  It  has  a  circular  band  one-eighth  of  an  inch  wide 
on  the  outer  surface  of  the  choroid  in  front.  The  radiating  fibers  are  more 
numerous  and  more  external  arising  from  the  sclerotic  close  to  the  junction  of 
the  sclerotic  and  the  cornea,  between  the  spaces  of  Fontana  and  the  canal  of 
Schlemn  and  pass  backward  to  be  inserted  in  the  choroid  opposite  the  ciliary 
processes.  The  circular  fibers  are  internal  to  the  radiating  at  the  base  of  the 
ciliary  processes  surrounding  the  iris. 

PLATE  CCII I. 


NASAL. 


SUPRAORBITAL 


TEMPORAL    yC^f 
BRANCHES  ^^T^f 


LACHRYMAL 


ARTERIA     CENTRALIS     RETINAE. 


OPHTHALMIC. 


ANT.     ETHMOIDAL. 


POST.    ETHMOIDAL. 


INTERNAL    CAROTID. 

Distribution  of  Ophthalmic  Artery. 

The  iris  is  a  thin,  fibrous,  and  contractile  circular  membrane  which  gives 
color  to  the  eye.  It  is  suspended  in  the  aqueous  humor  between  the  cornea  in 
front  and  the  lens  behind.  The  pupil  is  an  aperature  in  its  center.  It  is  con- 
tinuous at  the  circumference  with  the  choroid  and  anterior  to  this  it  is  connect- 
ed to  the  cornea  by  the  pillars  of  the  iris  or  Ligamentum  pectination.  It  is  also 
connected  to  the  ciliary  muscle.     The  uvea  or  the  posterior  surface  is  marked 


ANATOMY    IX    A    NUTSHELL.  H87 

with  folds  prolonged  from  the  ciliary  processes  and  is  darkly  pigmented.  The 
anterior  surface  is  colored  and  marked  by  wavy  lines  which  converge  towards 
the  free  edge  of  the  pupil.  This  surface  is  covered  by  a  layer  of  epithelium 
which  is  continuous  with  that  of  the  membrane  of  Descemet.  The  frame  work 
of  the  iris  is  a  delicate  struma  which  consists  of  connective  tissue  containing 
blood  vessels,  nerves,  pigment  cells,  and  muscular  fibers  (involuntary).  The 
first,  sphincter  fillers  which  form  a  circular  narrow  band  pass  to  the  pupil  and 
receive  the  third  nerve.  This  band  is  about  one-thirtieth  of  an  inch  in  thick- 
ness. The  second,  dilator,  which  are  radiating,  commence  at  the  outer  margin 
of  the  iris,  converging  towards  its  center  to  join  the  circular  one  near  the  pupil. 
Some  say  these  are  elastic  and  not  muscular.  It  receives  the  sympathetic 
nerve.  The  blood  supply  is  from  the  Long  and  anterior  ciliary  and  the  vessels 
of  the  ciliary  processes.  Nerve  supply  from  the  ciliary  branches  of  the  lenticu- 
lar ganglion  and  long  ciliary  branches  of  the  nasal  nerve  which  is  a  branch  of  the 
ophthalmic  division  of  the  fifth.  The  nerves  form  a  plexus  around  the  mar«in. 
The  membrana  pupillaris  is  a  delicate  transparent  vascular  membrane  which 
closes  the  pupil  in  the  fetus.     It  disappears  about  the  seventh  month. 

The  retina  ends  behind  the  ciliary  muscle  in  an  irregular  margin,  the  ora 
serrata.  The  pars  ciliaris  (radiating  fibers  of  Muller  covered  bv  pigmented 
layers)  is  a  thin  membrane  passing  from  the  ora  serratus  to  the  iris.  The 
macula  lutea  is  the  most  perfect  point  of  vision.  It  is  situated  at  the  center  of 
its  inner  surface  behind.  It  has  a  depression  called  the  fovea  centralis.  The 
poms  opticus  of  the  optic  nerve  is  pierced  by  the  arteria  centralis  retinae  and  is 
one-tenth  of  an  inch  internal  to  the  macula  lutea.  Mutter's  fibers  are  connective 
tissue  fibers  which  bind  the  layers  of  the  retina  together.  The  aqueous  humor 
fills  the  anterior  and  posterior  aqueous  chambers  which  are  situated  between 
the  posterior  surface  of  the  cornea  and  the  anterior  surface  of  the  iris  and  be- 
tween the  posterior  surface  of  the  iris  and  the  anterior  surface  of  the  crystalline 
lens.  It  is  a  slightly  alkaline  fluid.  The  lens  is  in  contact  anteriorly  with  the 
iris:  posteriorly  it  rests  in  the  depression  of  the  vitreous  humor,  fovea  pupillaris. 
It  is  surrounded  by  a  capsule-zonule  of  Zinn  which  is  derived  from  the  hyaloid 
membrane.  The  lens  is  about  one-fourth  of  an  inch  antero-posteriorly  and  one- 
half  transversely.  It  is  a  transparent,  solid,  biconvex  body  composed  of  con- 
centric laminae  and  is  hardest  at  the  center.  The  vitreous  humor  occupies  about 
four-fifths  of  the  eye-ball  resting  upon  the  retina  behind  and  is  hollowed  out  in 
front  the  fossa  pupillaris  for  the  lens.  It  is  a  soft,  gelatinous  substance  and 
surrounded  by  transparent  hyaloid  membrane.  It  fills  the  cavity  of  the  re- 
tina. The  canal  of  Stilling  runs  through  its  center  from  the  porus  opticus  to 
the  lens  and  is  lined  by  a  prolongation  of  the  hyaloid  membrane.  This  canal 
is  filled  with  fluid.  In  the  fetus  an  artery  runs  from  the  arteria  centralis  retina' 
to  the  capsule  of  the  lens.  At  the  pars  ciliaris  this  membrane  divides  sending 
a  layer  behind  the  capsule  and  one  in  front:  the  anterior  one  is  the  suspensory 
ligament  of  the  lens.  It  contains  elastic  fibers.  The  canal  of  Petit  surrounds 
the  lens.     (Plate  CC). 

The  lachrymal  gland  (Plate  CCV)  resembles  serous  salivary  glands.  It  is  situated 
internal  to  the  external  angular  process  in  a  depression  in  the  orbital  plate  of 


388 


ANATOMY    IN    A    NUTSHELL. 


the  frontal  bone  resting  on  the  eye-ball  and  the  Superior  rectus  and  External 
rectus  muscles.  It  is  about  the  shape  and  size  of  an  almond.  It  is  constricted 
in  ihf  center.  The  ducts,  about  seven,  pass  through  the  conjunctiva,  opening 
on  the  outer  part  of  the  upper  lid.  The  lachrymal  canals,  two  in  number,  begin 
at  the  puncta  lachrymalia  in  each  lid,  the  superior  one  passing  upward  and  then 
inward  to  join  the  inferior  one  which  passes  downward  and  then  inward.  They 
empty  into  the  lachrymal  sac  together.  The  lachrymal  sac  lies  in  a  groove 
formed  by  the  lachrymal  bone  and  nasal  process  of  the  superior  maxillary.  It 
is  the  dilated  upper  part  of  the  nasal  duct.  It  is  crossed  by  the  Tensor  tarsi  and 
is  covered  by  an  expansion  from  the  tendo  oculi.  The  duct  is  about  one-half 
an  inch  long  and  directed  downward,  slightly  outward  and  backward.  It  is 
formed  by  the  lachrymal,  superior  maxillary,  and  inferior  turbinated  bones.  It 
extends  from  the  lachrymal  to  the  inferior  meatus  of  the  nose  where  it  opens. 
The  opening  has  a  valve  formed  by  the  mucous  membrane. 

PLATE  CCIV. 


MOALJJNE 
OPTICAL.         AXJS 


FOVEA  CENTRALIS 
OR  CENTRAL  PIT 

OF  THE 
MACULA  LUTEA. 


Optical  Axis  and  Visual  Line. 


LESSON  CVIX. 

The  conjunctiva  (joined  together)  which  unites  the  eyelids  and  the  eye-ball 
is  a  mucous  membrane.  It  lines  each  eyelid  at  the  base  of  which  it  is  reflected 
mi  the  eye-ball.  The  lines  of  reflection  are  the  fornices.  The  supeiior  one  is 
the  deeper  and  some  of  the  fibers  of  the  Levator  palpebral  are  inserted  into  it. 
The  conjunctiva  is  loosely  attached  to  the  sclerotic  cord,  but  at  the  outer  mar- 
gin of  the  cornea  it  is  firmly  attached,  passing  over  the  cornea,  forming  its  in- 
ferior epithelial  layer.  The  ducts  of  the  lachrymal  gland  open  into  the  con- 
junctival sac  above  and  the  opening  of  the  lachrymal  canaliculi  at  the  puncta 
lachyrymalia  below.  The  palpebral  conjunctiva  is  sensitive,  vascular  and 
thick.  Pari  of  the  eye-ball  or  ocular  conjunctiva  is  thin, transparent  and  is  only 
slightly  vascular  in  the  healthy  condition.  The  plica  semilunaris  is  a  fold  of 
conjunctiva  at  the  inner  canthus  of  the  eye.  It  is  the  rudimentary  homologue 
of  the  membrana  Nictitans  (third  eyelid)  in  birds.      (Plates  CCV-CCIX). 


ANATOMY    IN    A    NUTSHELL.  389 

The  eyebrows  (supercilia)  are  two  arched  eminences  over  each  orbitc,on- 
sisting  of  thickened  integument  and  muscles  and  are  covered  by  thick  hairs. 
Each  one  is  connected  with  the  Orbicularis  palpebrarum,  Corrugator  super- 
cilii,  and  Occipito-frontalis. 

Eyelids.  The  upper  one  is  more  movable  than  the  lower  one.  When 
closed  they  protect  the  eye-ball  from  injury.  Where  the  upper  and  lower  lids 
meet  when  open  they  form  the  outer  and  inner  canthus.  The  lacus  lachrymaiis 
is  a  small  triangular  area  in  the  inner  canthus  in  which  is  a  mass  of  fat  (pink) 
connective  tissue.  This  mass  is  caruncula  lachrymaiis  and  it  is  separated  from 
the  eye-ball  by  a  vertical  fold  of  conjunctiva,  the  plica  semilunaris  which  is  a 
rudimentary  third  eyelid. 

The  eyelashes  (cilia)  are  short,  thick  hairs  which  form  a  double  row  at  the 
free  margin  of  each  lid.  Those  of  the  upper  lid  are  longer  and  more  numerous 
than  those  of  the  lower  lid.  Each  eyelid  has  the  following  structures  from  with- 
out inward:  (1)  Skin,  (2)  areolar  tissue,  (3)  Orbicular  muscle,  (4)  tarsal 
plate,  (5)  palpebral  ligament,  (6)  Meibomian  glands,  (7)  conjunctiva.  The 
upper  lid  has  in  addition  the  aponeurosis  of  the  Levator  palpebral  which  is  at- 
tached to  the  upper  surface  of  the  tarsal  plates. 

The  tarsal  plates  are  in  each  lid  and  are  formed  by  lamina  of  a  dense  con- 
nective tissue.  The  upper  one  is  the  larger;  it  is  half  oval  in  shape  while  the 
lower  one  is  a  narrow  oblong  slit. 

The  Meibomian  glands  are  lodged  in  these  plates.  The  palpebral  ligaments 
are  at  the  outer  and  inner  angle  of  the  eye,  forming  attachments  for  the  Orbi- 
cularis palpebrarum  muscle.  They  form  an  imperfect  diaphragm  for  the  anterior 
orifice  of  the  orbit.  Peripherally  they  are  attached  to  the  orbital  margin  and 
centrally  to  the  edges  of  the  tarsal  plates.     (See  Plate  CCXII.) 

The  third  or  motor  oculi  has  its  superficial  origin  in  front  of  the  pons  on 
the  inner  side  of  the  crus  cerebri.  Its  deep  origin  is  situated  on  each  side  of  the 
median  line  on  the  floor  of  the  aqueduct  of  Sylvius,  after  passing  through  the 
substantia  nigra  and  the  tegmentum  of  the  crus.  All  the  muscles  of  the  orbital 
region  are  supplied  by  the  third  nerve  except  the  Superior  oblique,  which  re- 
ceives the  fourth  nerve  and  the  External  rectus,  which  receives  the  sixth.  This 
nerve  also  supplies  the  sphincters  of  the  iris  and  the  ciliary  muscle  through  its 
connection  with  the  ciliary  ganglion.  Remember  that  the  External  rectus  of 
one  eye  and  the  Internal  rectus  of  the  other  eye  have  their  nerve  supply  from 
the  same  nucleus.  The  nucleus  of  the  third  nerve  receives  the  fibers  from  that 
of  the  sixth  nerve  of  the  opposite  side;  this  accounts  for  the  fact  that  one  can 
move  both  eyes  to  the  right  or  left  at  the  same  time.  From  this  deep  origin 
of  the  third  nerve  each  muscle  supplied  by  it  has  its  own  set  of  cells.  Then  from 
behind  forward  their  position  is  (1)  those  cells  to  the  Internal  rectus;  (2)  to  the 
Levator  palpebral;  (3)  the  Superior  rectus;  (4)  the  Inferior  rectus;  ami  (">)  the 
Inferior  oblique.  In  front  of  these  are  the  nuclei  of  the  fibers  for  accommoda- 
tion and  for  sphincter  pupillae.  It  is  covered  with  pia  mater  and  arachnoid  on 
leaving  the  brain.  It  pierces  the  dura  mater  anterior  and  external  to  the  pos- 
terior clinoid  process  after  having  passed  between  the  superior  cerebellar  and 
the  posterior  cerebral  arteries.     It    then   passes   through   the  cavernous  sinus 


390 


ANATOMY    IN    A    NUTSHELL. 


above  the  other  orbital  nerves.  In  this  position  it  communicates  with  the 
ophthalmic  division  of  the  fifth  and  with  the  cavernous  plexus.  Before  enter- 
ing the  sphenoidal  fissure  it  divides  into  two  branches,  a  superior  and  an  in- 
ferior one,  with  the  nasal  branch  of  the  fifth  nerve  between  them.  (Plate 
(  CXXIV).  All  the  structures  on  the  Lower  border  of  the  sphenoidal  fissure  are  be- 
tween tlif  two  heads  of  the  External  rectus  muscle.  The  superior  branch  is  the 
smaller,  h  passes  forward  over  the  optic  nerve  and  supplies  the  Levator 
palpebrae  and  Superior  rectus  muscles.  The  inferior  branch  supplies  three 
muscles;  the  division  which  goes  to  the  Internal  rectus  passes  beneath  the  optic 
nerve;  the  second  division  passes  to  the  Inferior  rectus, and  the  third  or  lower 
division  passes  to  the  Inferior  oblique  between  the  External  rectus  and  the  In- 
ferior rectus.  This  division  to  the  Inferior  oblique  sendsa  motor  branch  to  the  In- 
ferior rectus.  The  branches  of  the  third  nerve  enter  their  muscles  on  the  orbital 
surface  except  the  branch  to  the  Inferior  oblique  which  enters  on  the  posterior 
1  inn  ler.     This  third  nerve  may  supply  the  anterior  belly  of  the  Occipito-frontalis, 

PLATE  CCV. 


DUCTS  OF  LACHRYMAL  GLAND. 


LACHRYAMAL  SAC 


CARUNCLE 


NASAL .DUCT 


Nasal  Duct,  Conjunctiva,  and  Lachrymal  Gland. 


the  Corrugator  supercilii,  and  the  Orbicularis  palpebrarum.  These  muscles 
are  generally  supplied  by  the  seventh,  but  they  have  escaped  paralyses  in  lesions 
of  the  nuclei  of  the  seventh  nerve.  From  the  nucleus  of  the  third  nerve  some 
fibers  which  descend  in  the  posterior  longitudinal  bundle  join  the  facial  nerve 
ju.-t  before  it  leaves  the  pons;  these  fibers  supply  the  three  muscles  above  men- 
tinned.  Paralyses  of  the  third  nerve  may  be  only  in  part  as  any  fibers  to  one 
muscle  or  it  may  be  the  whole  nerve.  When  the  whole  nerve  is  paralyzed  the 
following  result :  (1 )  Prominence  of  the  eye-ball  because  most  of  the  mus- 
cles are  relaxed.  (2)  Extern  vl  strabismus,  the  eye-ball  being  drawn  outward 
because  the  External  rectus  which  is  supplied  by  the  sixth  is  not  paralyzed. 
(3)  Ptosis  because  the  Levator  palpebrae  is  paralyzed.  (4)  Loss  of  accommoda- 
tion because  the  [nternal  rectus,  the  ciliary  muscle,  and  the  sphincter  pupillse 
are  paralyzed.  (5)  Dilatation  of  the  pupil  because  the  sphincter  fibers  of 
the  iris  are  paralyzed. 


ANATOMY    IN    A    NUTSHELL. 


391 


LESSON  CX.  (Plate  CCXIII). 

The  fourth  cranial  nerve  or  Pathetic  or  Trochlear,  has  its  superficial 
origin  in  the  valve  of  Vieussens  behind  the  corpora  quadrigemina.  The  two 
nerves  decussate  on  the  upper  surface  of  the  valve.  Its  deep  origin  is  in  the 
floor  of  the  aqueduct  of  Sylvius.  This  nerve  can  be  seen  on  the  base  of  the  brain 
on  the  outer  side  of  the  cms  cerebri,  just  in  front  of  the  pons.  It  is  the  smallest 
of  all  the  cranial  nerves  but  has  the  longest  intercranial  course.  Coming  from 
the  upper  end  of  the  valve  of  Vieussens  this  nerve  crosses  the  superior  peduncles 
of  the  cerebellum  and  the  crusta  of  the  mid-brain,  just  beneath  the  pons,  then 
it  pierces  the  dura  mater  in  the  free  border  of  the  tentorium,  immediately  be- 
hind and  external  to  the  posterior  clinoid  process.  From  this  point  it  passes 
forward  in  the  outer  wall  of  the  cavernous  sinus  between  the  third  nerve  and  the 
ophthalmic  division  of  the  fifth  (See  Plate  CCXXXII) ;  it  then    crosses    the 

PLATE  CCVI. 


TARSAL  CARTILAGE 


The  Muscles  of  the  Orbital  Region. 


third  nerve  and  enters  the  orbit  through  the  sphenoidal  fissure  (anterior  Lacer- 
ated); in  this  fissure  it  is  the  highest  of  all  the  nerves  (See  Plate  CCXXIV) 
being  situated  at  the  upper  and  inner  angle,  internal  to  the  frontal  nerve.  In 
the  orbit  it  passes  inward  above  the  origin  of  the  Levator  palpebrae  to  enter  the 
orbital  surface  of  the  Superior  oblique.  In  the  cavernous  sinus  it  communi- 
cates with  the  ophthalmic  division  of  the  fifth,  with  the  ciliary  plexus,  and  semis 
a  recurrent  branch  backward  between  the  layers  of  the  tentorium  as  far  as  the 
lateral  sinus.  While  in  the  anterior  lacerated  fissure  it  may  send  a  branch  to 
the  lachrymal  nerve.  If  the  fourth  nerve  is  paralyzed  the  function  of  the 
Superior  oblique  is  lost  and  one  cannot  turn  the  eye-ball  now  \\\  \ki>  \\n  out- 
wai;i>.  Should  one  attempl  to  do  so  the  eye  is  twisted  inward  producing  double 
vision,  diplopia. 


392 


ANATOMY    IN    A    NUTSHELL. 


The  sixth  nerve  or  Abducent  has  its  superficial  origin  from  the  lower  part 
of  the  pons  in  the  groove  between  the  pyramid  and  the  pons  or  in  the  constricted 
part  of  the  pyramid.  Its  deep  origin  is  in  the  floor  of  the  fourth  ventricle 
close  to  the  median  line  and  a  little  lower  than  that  of  the  motor  root  of  the 
fifth.  This  origin  is  traced  to  a  nucleus  under  the  upper  half  of  the  funiculus 
teres.  This  nerve  enters  the  cavernous  sinus  after  the  dura  mater  of  the  basilar 
process  of  the  sphenoid,  running  through  a  notch  immediately  below  the  pos 
terior  clinoid  process.  In  the  cavernous  sinus  it  lies  external  to  the  internal 
carotid  artery.  From  this  sinus  it  enters  the  orbit  between  the  two  heads  of 
the  External  rectus  to  supply  this  muscle,  entering  the  muscle  on  the  orbital 
surface. 


PLATE  CCVII. 


SUP.     RECTUS. 


INTERNAL  RECTUS. 


INf.    OBLIQUE. 


EXTERNAL  RECTUS. 


SUP.    -OBLIQUE. 


INF.     RECTUS.        'y 

Showing  the  Directions  that  Muscles  of  the  Eye-Ball  Move  the  Eye. 


For  its  position  in  the  sinus  (See  Plate  CCXXXII.)  All  the  structures  on 
the  floor  of  the  sphenoidal  fissure  lie  between  the  two  heads  of  the  External 
rectus.  For  position  of  the  nerves  in  the  orbit  (See  Plate  CCXV).  The 
fourth  nerve  lies  on  the  Superior  oblique,  the  frontal  nerve  on  the  Levator  pal- 
pebrae,  and  the  lachrymal  nerve  on  the  External  rectus.  The  superior  division 
of  the  third  nerve  lies  along  the  Superior  rectus;  the  nasal  nerve  crosses  the  optic 
nerve  from  without  inward:  the  optic  nerve  is  surrounded  anteriorly  by  the 
ciliary  nerves;  the  lenticular  ganglion  lies  between  the  optic  nerve  and  the  Ex- 
ternal rectus.  The  sixth  nerve  is  on  the  outer  surface  of  the  orbit.  The  in- 
ferior division  of  the  third  nerve  is  below  the  lenticular  ganglion  and  this  nerve 
is  joined  by  filaments  from  the  cavernous  plexus,  carotid  plexus,  and  the  ophthal- 
mic nerve.  If  the  sixth  nerve  is  paralyzed  internal  or  convergent  squint 
follows  as  the  External  rectus  loses  its  function.  The  pupil  is  contracted  to 
some  extent  in  paralysis  of  this  nerve  as  some  of  the  sympathetic  fibers  to  the 
radiating  muscle  of  the  iris  pass  along  this  nerve. 

The  fifth  nerve  is  the  largest  of  the  cranial  nerves.  It  is  more  like  a  spinal 
nerve  than  any  other  of  the  cranial  nerves.     It  is  a  compound  nerve,  having 


ANATOMY    IN    A    NUTSHELL. 


393 


an  anterior  or  motor,  and  a  posterior  or  sensory  root  with  a  ganglion  upon  it. 
It  is  called  the  trifacial  or  trigeminus,  lis  superficial  origin  is  on  the 
side  of  the  pons,  nearer  the  upper  than  the  lower  border.  Its  motor  fibers, 
which  are  three  or  four  bundles,  are  separated  from  the  sensory  fibers,  which 
are  seventy  to  one  hundred  bundles,  by  a  few  transverse  fibers.  The  deep 
origin  is  in  the  floor  of  the  fourth  ventricle.  Its  sensory  portion  is  in  a  nucleus 
in  the  pons  just  below  the  floor  and  just  beyond  the  margin  of  the  upper  half 
of  the  fourth  ventricle.  The  motor  portion  is  a  nucleus  internal  to  the  sensory 
and  external  to  the  funiculus  teres  on  the  upper  half  of  the  floor.  (Plates  CCXIY- 
CCXV). 

PLATE  CCVTII. 


2ND 


Showing  Refraction  of  Light  Through  Crystalline  Lens. 


It  is  the  sensory  nerve  to  the  head  and  face,  and  a  motor  NERVE  to  the 
muscles  of  mastication.  Its  roots  pass  through  an  oval  opening  in  the  dura  mater 
near  the  apex  of  the  petrous  portion  of  the  temporal  bone.  The  senBory  root 
is  from  the  Gasserian  ganglion,  which  is  situated  in  Meckel's  cave.  This  cave 
is  a  depression  near  the  apex  of  the  anterior  surface  of  the  petrous  portion  of  the 
temporal  bone.  The  anterior  or  motor  root  passes  under  the  Gasserian  ganglion 
and  is  not  joined  to  it  but  joins  the  inferior  maxillary  division  of  the  fifth  after 
it  passes  through  the  foramen  ovale,  thus  making  this  pari  of  the  nerve  a  coin- 
pound  nerve;  in  fact  it  is  the  only  pari  of  the  fifth  nerve  which  is  a  compound 
nerve  for  the  other  two  divisions  are  purely  sensory.  This  ganglion  gives  off 
from  its  anterior  edge  three  trunks.  (1)  Ophthalmic,  (2)  Superior  maxillary,  and 
(3)  Inferior  maxillary.  It  sends  communicating  branches  to  the  carotid  plexus, 
tentitorium.  cerebellum,  and  the  dura  mater  of  the  middle  fossa. 


394 


ANATOMY    IN    A    NUTSHELL. 


I.  The  ophthalmic  branch  purely  sensory,  is  the  smallest  and  courses  along 
the  outer  wall  of  the  cavernous  sinus  below  the  third  and  fourth  nerves.  It 
divides  into  three  branches  which  leave  the  cranium  through  the  anterior  lacer- 
ated or  sphenoidal  fissure.  (For  relation  of  these  branches  see  Plate  CCXXIV.) 
These  branches  are  the  frontal,  nasal,  and  lachrymal.  The  ophthalmic  sup- 
plies the  eye-ball,  the  lachrymal  gland,  the  orbital  and  nasal  mucous  membrane 
and  skin  of  the  eyebrow,  forehead,  and  nose. 

The  frontal  branch  is  the  largest  and  is  just  external  to  the  fourth  nerve 
and  the  anterior  lacerated  or  sphenoidal  fissure  and  passes  forward  on  the  Leva- 
tor palpebral  dividing  into  two  branches. 

PLATE  CCTX. 

SUPERIOR  FORNIX 


UPPER  LID 


LOWER  LID 


INFERIOR  FORNIX 

Superior  Fornix  and  Inferior  Fornix  of  Conjunctiva. 


LESSON  CXI. 

(a)  The  supraorbital  which  passes  through  the  supraorbital  foramen  or 
notch.  It  gives  a  branch  to  the  diplce  and  mucous  membrane  of  the  frontal 
sinus.  The  outer  and  inner  branches  supply  twigs  to  the  pericranium  and 
pierce  the  Frontalis  muscle.  They  communicate  with  branches  from  the  facial 
nerve  and  are  distributed  to  the  skin  of  the  scalp  in  the  frontal  and  parietal 
regions.  The  outer  branch  is  the  larger  and  passes  backward  almost  to  the 
lambdoid  suture. 

(b)  The  supratrochlear  nerve  is  the  smaller  and  passes  inward  above 
tin'  pulley  of  the  Superior  oblique  and  sends  a  branch  to  join  the  infratrochlear 
branch  of  the  nasal.  It  Leaves  the  orbit  between  the  supraorbital  foramen  and 
the  pulley  and  passes  upward  under  cover  of  the  Corrugator  supercilii  and 
( >ccipito-frontalis  to  supply  the  skin  of  the  lower  part  of  the  forehead  near  the 
midline. 

The  lachrymal  is  the  smallest  branch.  It  passes  to  the  under  surface  of 
the  lachrymal  gland  where  ii  joins  the  orbital  of  the  superior  maxillary,  form- 
ing a  loop  which  sends  branches  into  the  gland.     It  passes  through  the  sphenoid- 


ANATOMY    IN    A    NUTSHELL. 


395 


al  fissure  external  and  below  the  frontal  nerve  and  passes  along  the  upper  bor- 
der of  the  External  rectus  muscle.  It  then  pierces  the  palpebral  fascia  and 
supplies  the  conjunctiva  and  integument  at  the  outer  canthus  of  the  eye  and 
that  over  the  external  angular  process. 

The  nasal  branch  is  the  third  division  of  the  ophthalmic  division  of  the 
fifth.  It  passes  into  the  orbit  between  the  two  divisions  of  the  third  nerve  on 
the  floor  of  the  sphenoidal  fissure.  In  the  orbit  it  passes  from  the  outer  to  the 
inner  side  over  the  optic  nerve,  below  the  Superior  rectus,  then  it  passes  between 
the  Superior  oblique  and  Internal  rectus  to  leave  the  orbit  through  the  anterior 
ethmoidal  foramen  with  the  anterior  ethmoidal  vessels  into  the  cranium.  In 
the  cranium  it  passes  forward  outside  of  the  dura  mater,  which  separates  it 
from  the  Levator  palpebral  to  pass  through  the  nasal  slit  into  the  nasal  fossa 
where  it  divides  into  its  three  terminal  branches. 

PLATE  CCX. 


CILIARY  PROCESSES. 
AND    MUSCLE^ 


SUSPENSORY         LIGAMENT. 


Crystalline  Lens. 


(a)  Internal  or  septal  branch,  which  is  distributed  to  the  upper  and 
front  of  nasal  septum,  (b)  External  branch  to  superior  and  middle  turbinated 
bones  and  to  the  mucous  membrane  of  the  outer  wall  of  the  nose,  (c)  Anterior 
branch  runs  in  the  groove  on  the  inner  surface  of  the  nasal  bone.  It  pierces  the 
wall  of  the  nose  between  the  nasal  bone  and  the  upper  lateral  cartilage  and  sup- 
plies the  integument  of  the  lower  part  of  the  dorsum  of  the  nose  as  far  as  the  tip. 

The  nasal  nerve  gives  off  the  following  collateral  branches: 

1.  The  long  root  to  the  ciliary  ganglion  which  runs  forward  on  the  outer 
side  of  the  optic  nerve  to  the  upper  and  back  part  of  the  ciliary,  lenticular,  or 
ophthalmic  ganglion. 

2.  Long  ciliary  branches,  two  or  three  in  number,  pass  along  the  inner 
side  of  the  optic  nerve, join  the  short  ciliary  branch  from  the  ganglion,  thru 
pierce  the  sclerotic  coat  to  be  distributed  to  the  ciliary  muscle,  the  iris,  and  the 
cornea. 

3.  Infratrochlear  nerve  is  given  off  just  before  the  nasal  nerve  passes 
between  the  Superior  oblique  and  Internal  rectus.  It  communicates  with  the 
Supratrochlear  and  is  distributed  to  the  skin  of  the  eyelid  and  side  of  the  nose, 
conjunctiva,  lachrymal  sac,  and  caruncula  lachrynialis. 

This  lenticular,  ciliary,  or  ophthalmic  ganglion  has  three  roots. 


396 


ANATOMY    IX    A    NUTSHELL. 


A  MOTOR  ROOT  from  the  third  nerve,  sympathetic  root  from  the  cavernous 
plexus,  and  a  sensory  root  from  the  nasal.  Its  branches  are  distributed  to 
the  iris,  ciliary  muscle,  and  cornea. 

11.  The  superior  maxillary  division  of  the  fifth  is  intermediate  in  size  and 
position  between  the  ophthalmic  and  inferior  maxillary  division.  It,  like  the 
ophthalmic  branch,  is  purely  sensory.  It  comes  from  the  anterior  part  of  the 
Gasseriarj  ganglion  and  passes  through  the  cavernous  sinus  in  the  lower  and 
outer  part;  it  then  leaves  the  cranium  through  the  foramen  rotundum,  entering 

PLATE  CCXI. 


CANAL  OF  SCHLEMN 


CILIARY  BODY 
CILIARY  PROCESSES 


EXTERNAL  RECTUS 


CHOROID  COAI 


POSTERIOR  CHAMBER. 
CANAL    OF  PETIT 

NTERNAL  RECTUS  MUSC1 


NERVE  SHEATH 


A  Horizontal  Section  of  the  Eye-Ball. 


the  Bpheno-maxillary  fossa  where  it  is  connected  with  Meckel's  ganglion.  As 
it  passes  forward  it  is  called  the  infratrochlear  nerve  and  passes  in  the  groove  on 
the  floor  of  the  orbit  and  comes  out  on  the  face  through  the  infraorbital  foramen. 
This  foramen  is  beneath  the  Levator  labii  superioris  and  the  Levator  anguli- 
oris.     The  nerve  in  this  position  anastomoses  with  the  seventh  to  form  a  plexus 


ANATOMY    IX    A    NUTSHELL. 


397 


which  gives  off  three  branches,  (1)  palpebral,  (2)  nasal,  and  (3)  labial. 
While  in  the  sphenomaxillary  fossa  it  is  in  relation  with  the  infraorbital  artery 
which  accompanies  it  on  its  course  to  the  face.  The  branches  of  distribution  are: 
(1)  those  given  off  in  the  cranium;  (2)  those  given  off  in  the  spheno-maxillarv 
fossa;  (3)  those  given  off  in  the  infraorbital  canal:  and  (4)  those  given  off  on  the 
face. 

Those  in  the  cranium  are  one  or  two  meningeal  branches  which  unite  with 
the  recurrent  branch  of  the  inferior  maxillary  division  of  the  fifth  and  also  with 
the  sympathetic  nerve  around  the  meningeal  artery  which  accompanies  it  to 
the  dura  mater. 

PLATE  CCXII. 


LEVATOR  PALPEBRAE 


RECTUS  SUPERIOR; 


RECTUS  INFERIOR 
RECTUS  INTERNUS. 

INFERIOR  OBLIQUE, 


The  Third  Cranial  or  Motor  Oculi  Nerve. 


In  the  spheno-maxillarv  fossa  are,  1.  Orbital  or  temporo-nialar  branch 
which  passes  upward  and  forward  to  enter  the  spheno-maxillarv  fissure  where 
it  divides  into  temporal  and  malar  branches. 

The  temporal  branch  passes  upward  in  a  groove  in  the  outer  wall  of  the 
orbit  where  it  receives  a  branch  from  the  lachrymal  before  it  traverses  the 
Bpheno-malar  foramen  to  enter  the  temporal  fossa.  It  turns  round  the  anterior 
border  of  the  temporal  fascia,  then  running  forward  and  outward  to  pierce  its 
fascia  about  an  inch  above  the  zygoma  to  anastomose  with  the  seventh  and 
auiiculo-teniporal  of  the  inferior  maxillary  division  of  the  fifth,  and  supplies 
the  skin  of  the  anterior  part  of  the  temporal  region. 

The  malar  branch  (subcutaneous  mala?)  supplies  the  skin  on  the  promi- 
nence of  the  cluck  after  passing  along  the  external  inferior  angle  of  the  orbit 
through  the  foramen  in  the  malar  bone  where  it  perforates  the  Orbicularis 
palpebrarum  muscle. 

2.  The  spheno-palatine  branches  are  two  in  number  and  descend  to  the 
Bpheno-palatine  or  Meckel's  ganglion  but  do  not  end  there,  for  most  of  the  fibers 
pass  into  the  palatine  nerves. 


398 


ANATOMY    IN    A    NUTSHELL. 


3.  The  third  set  are  (1)  the  posterior  superior  dental,  usually  two  in 
number.  They  pass  downward  and  outward  through  the  ptery go-maxillary 
fissure  into  the  zygomatic  fossa  where  they  give  branches  to  the  mucous  mem- 
brane of  the  gums  and  the  posterior  part  of  the  mouth.  They  then  enter  the 
posterior  dental  canals  on  the  zygomatic  surface  of  the  superior  maxillary  bone 
to  communicate  with  the  middle  dental  nerve  and  branches  to  the  lining  mem- 
brane of  the  antrum  of  Highmore  (superior  maxillary  sinus).  It  also  gives  off 
three  branches  to  the  molar  teeth  which  enter  the  foramina  at  the  apices  of  the 
fangs  to  supply  the  pulp. 

(b)  The  middle  superior  dental  and  the  anterior  superior  dental  are 
given  off  in  the  infraorbital  sulcus.  The  middle  supplies  the  bicuspid  teeth 
and  the  mucous  membrane  of  the  antrum  and  the  gums.  After  leaving  the 
infraorbital  nerve  it  passes  downward  and  forward  in  a  canal  in  the  superior 
maxillary.  These  branches  which  supply  the  teeth  anastomose  with  the  anter- 
ior superior  and  posterior  superior  dental  branches.  At  the  junction  of  the 
middle  and  anterior  is  the  ganglion  of  Bochdalek;  at  the  junction  of  the  middle 
and  posterior  is  the  ganglion  of  Valentin. 

PLATE  OCX  III. 


RECURRENT  TO  SYMPATHETIC- 

The  Trochlear  or  Fourth  Cranial  Nerve. 
LESSON  CXII. 


(c)  The  anterior  superior  branch  is  given  off  just  before  the  infraorbital 
nerve  enters  the  infraorbital  foramen.  It  descends  to  supply  the  incisor  and 
canine  teeth.  It  gives  branches  to  the  gums  and  mucous  membrane  of  the 
antrum  and  the  nasal  branch  which  enters  the  nasal  fossa  through  a  small 
foramen  and  supplies  the  mucous  membrane  of  the  forepart  of  the  inferior 
meatus  and  its  floor.  It  communicates  with  the  nasal  branch  from  Meckel's 
ganglion. 

The  branches  on  the  face  are  palpebral,  labial,  and  nasal. 

The  palpebral  supplies  the  skin  and  mucous  membrane  of  the  lower  eye- 
lid. At  the  outer  angle  of  the  orbil  it  joins  with  the  seventh  and  malar  branch 
of  the  orbital. 


ANATOMY    IN    A    NUTSHELL. 


399 


The  nasal  branch  passes  inward  and  upward  under  cover  of  the  Levator 
labii  superioris  to  supply  the  skin  on  the  posterior  part  of  the  lateral  aspect  of 
the  nose.     It  joins  with  the  nasal  branch  of  the  ophthalmic. 

The  labial  branch  descends  beneath  the  Levator  labii  superioris  to  be 

distributed  to  the  integument  of  the  upper  lid,  also  to  mucous  membrane  of 

mouth  and  to  labial  glands. 

» 

PLATE  CCXIV. 


TO  TENTORIUM    CEREBELLI. 


...            LESTICULARJiANGLION.  ,GASSEPIAV    JJTRIFAPAL 

^ /  V  ^ ^—  &  r.auni  mil  / 


--      u  -■-  HATES 

FROM  CARVERNOUS  PLEXUS. 
FROM     3RD.  NERVE. 


MOTOR  ROOT 
GREAT    SUPERFICIAL  PETROSAL.  FROM  7JH    NERVE. 

GREAT  DEEP  PETROSAL.   FROM  CAROTID  PLEXUS. 


J     C.  WITH  AURICULOTEMPORAL. 


AURICULOTEMPORAL 
TOFACIAL 

TO  TEMPORO-MAXILLARY  JOINT. 
TO  MEATUS-AUDITORIUS. 

MALL  SUPERFICIAL  PETROSAL  FROM    THE    FACIAL* 
STMP.  ON  MIDDLE  MENINGEAL. 
CC4.  XT0  TENSOR  PALATI 


^Vr  INFERIOR 

FROM  SYMPATHETIC  ON  FACIAL  ARTERY. 


TO  INTERNAL  PTERYGOID 


TO    TENSOR  TYMPANI. 


JWT.  BELLY  OF  DIGASTRIC. 


Showing  Branches  of  the  Fifth  Cranial  Nerve. 

III.  The  inferior  maxillary  division  of  the  fifth,  the  mandibular  branch, 

is  a  compound  nerve  after  it  passes  through  the  foramen  ovale.  It  is  the  largesl 
branch  of  the  fifth  nerve.  Its  sensory  portion  comes  from  the  Gasseriau  gang- 
lion. This  compound  nerve,  immediately  after  it  leaves  the  foramen  ovale, 
divides  into  anterior  and  posterior  branches.  The  main  trunk  before  it  divides 
has  the  External  pterygoid  muscle  and  optic  ganglioD  external,  and  the  Tensor 
palati  muscle  internal,  and  in  front  of  it  is  the  posterior  border  of  the  Internal 
pterygoid  muscle,  and  behind  is  the  middle  meningeal  artery.  The  branches 
from  the  trunk  are  (1)  a  recurrent  which  passes  backward  with  the  middle 
meningeal  artery  through  the  foramen  spinosum  to  supply  the  dura  mater. 

2.  The  nerve  to  the  Internal  pterygoid  muscle.     This  nerve  sends  a  motor 
branch  to  the  optic  ganglion.     The  anterior  division  of  the  main  nerve  is  small 


400 


ANATOMY    IN   A    NUTSHELL. 


ami  chiefly  motor  ami  gives  off  a  masseteric  branch  which  accompanies  the 
ter  artery  through  the  sigmoid  notch  of  the  inferior  maxillary  bone  to  be 
distributed  to  the  Masseter  muscle.     It  gives  a  twig  to  the  tempcro-mandi- 
1  nilar  articulation. 

3.  Deep  temporal  branches,  two  or  three  in  number,  which  lies  be- 
tween the  bone  and  the  upper  border  of  the  External  pterygoid  muscle  to 
end  in  the  deep  surface  of  the  Temporal  muscle.  The  anterior  one  is  from  the 
Buccal  to  supply  the  front  of  the  Temporal  muscle.     The  middle  one  to  supply 

PLATE  CCXV. 


SUPRATROCHLEAR  N, 

SUPRAORBITAL  N 
PULLEYOF  SUPERIOR  OBLIQUE  M 


TENDON  OF  SUP   OBLIQUE 

TAHSAL  CARTILAGE 
OF  UPPER  EYELID 
LACHYMAL  GLAND 
.OOP  BETWEEN  ORBITAL 

AND 
LACHRYMAL     NERVES 


LEVATOr,  PALPEBRAL  M. 
SUPERIOR  RECTUS 
FRONTAL  N. 


INTERNAL  RECTUS  M. 
OPTIC  N. 

SHORT  CILIARY  NERVES. 
ASAL  N. 

LENTICULAR  GANG  LION 


INFERIOR  OBLIQUE  M 
PALFEBRAL  BRANCH 


NASAL  BRANCH 
LABIAL  BRANCH 


ANT. 
.SUPERIOR  DENTAL  N. 
AN  D  A 

MIDDLE 
SUPERIOR     DENTAL  A 
AND  N 


GINGIVAL  A. 


INCISIVE  BR._ 


EXTERNAL  RECTUS  M. 
INFERIOR   RECTUS  M. 
LACHRYMAL  N. 
THIRD  N. 
FOURTH  NERVE. 
SIXTH     NERVE. 
OPHTHALMIC  DIV.  OF  5TH  N 
SUPERIOR  MAXILLARY  N 
GASSERIAN  GANGLION. 
HENO-PALATINEN. 
IAN     N. 
AURICULOTEMPORAL  N 

INFERIOR  MAXILLARY  N 
SMALL  MENINGEAL  A 


MIDDLE  MENINGEAL  A 
INTERNAL  MAXILLARY  A. 

NFERIOR  DENTAL  A. 

NFERIOR  DENTAL  N 


BUCCAL  A. 


0  A 
MYLO-HYOID  N 


MENTAL  N   MENTAL  A 


CHORDA-TYMPANI  N. 


Showing  Distribution  of  the  Fifth  Nerve  in  Reference  to  Other 

Structures. 


the  deep  part  of  the  Teiu ] >or;il  muscle  after  passing  above  the  External  ptery- 
goid. The  posterior  one  after  uniting  with  the  masseter  nerve  is  sent  to  the 
posterior  pari   <<\   the  Temporal  muscle. 


PLATE  CCXVI. 


SUPRATROCHLEAR  N 


INFRATROCHLEAR  N 


NASAL  N 


SUPRACLAVICULAR 
SHOWING  THE  CUTANEOUS  NERVE  SUPPLY  OF  HEAD  AND  NECK 


Showing  Cutaneous  Nerve  Supply  of  Head  \\i>  \i<  k. 

101 


402  ANATOMY  IN  A  NUTSHELL. 

4.  The  buccal  is  sensory  and  comes  out  between  the  two  heads  of  the  Ex- 
ternal pterygoid  to  reach  the  Buccinator  and  is  often  joined  to  the  anterior 
temporal  and  external  pterygoid  nerves.  It  communicates  with  the  seventh 
and  is  distributed  to  the  mucous  membrane  of  the  skin  of  cheek. 

5.  Branch  to  the  External  pterygoid  muscle  is  generally  adherent  to  the 
long  buccal  nerve.  The  posterior  branch  of  the  common  trunk  is  larger  and  is 
chiefly  sensory.  It  has  three  main  branches,  (a)  auriculo- temporal,  (b)  lingual 
which  is  purely  sensory,  but  (c)  the  inferior  dental  nerve  has  a  few  motor  fibers 
in  it  which  pass  to  the  Mylo-hyoid  muscle. 

6.  The  auriculotemporal  arises  by  two  heads  between  which  is  the  middle 
memingeal  artery.  It  then  passes  under  the  External  pterygoid  muscle,  over 
the  capsular  ligament  into  the  temporo-mandibular  joint.  From  here  upward 
with  the  temporal  artery  beneath  the  parotid  gland  to  the  temporal  fossa  where 
it  becomes  cutaneous  and  lies  posterior  to  the  superficial  temporal  artery.  It 
gives  off  seven  branches:  (a)  a  branch  to  facial  nerve,  (b)  a  branch  to  the  otic 
ganglion,  (c)  two  anterior  auricular  branches  distributed  to  tragus  and  upper 
and  outer  part  of  pinna,  (d)  superior  temporal  to  integument  of  the  greater  part 
of  the  temporal  region  and  they  anastomose  with  the  seventh,  (e)  auricular 
branch  to  temporo-maxillarv  articulation,  (f)  branches  to  external  auditory 
meatus,  which  branches  are  given  off  in  the  parotid  gland.  They  pass  between 
the  cartilage  and  the  bone  to  enter  the  meatus.  These  branches  supply  the 
upper  part  of  the  meatus,  tympanic  membrane,  and  occasionally  the  lobule, 
(g)  branches  to  the  parotid  gland. 

7.  LiNGUAL(gustatory)formerly  supposed  to  be  the  nerve  of  taste. so  it  was 
called  gustatory,  but  it  is  a  nerve  of  common  sensation  and  the  name  gustatory 
is  still  used  for  this  nerve.  It  lies  at  first  internal  to  the  External  pterygoid 
muscle  and  then  it  passes  downward  in  front  of  the  inferior  dental  nerve  and  is 
joined  at  an  acute  angle  by  the  chorda  tympani  nerve  from  the  seventh.  From 
here  L1  passes  downward  and  forward  between  the  Internal  pterygoid  and  the 
ramus,  over  the  Superior  constrictor  of  the  pharynx  on  the  Hyo-glossus  muscle, 
above  the  deep  part  of  the  submaxillary  gland  to  the  sides  of  the  tongue.  It 
has  (a)  communicating  branches  to  the  anterior  dental  nerve  and  submaxillary 
ganglion  and  the  twelfth  nerve,  and  (b)  branches  of  distribution  to  the  tongue. 

8.  TheiNFERiOR  dental  is  the  largest  branch  and  passes  downward  underthe 
External  pterygoid  muscle  posterior  to  the  lingual  nerve. then  to  the  dental  for- 
amen after  passing  between  the  ramus  and  internal  lateral  ligament.  It  passes 
through  the  dental  canal  to  emerge  at  the  mental  foramen.  This  nerve  has  four 
main  sets  of  branches,  (a)  Those  to  the  Mylo-hyoid  muscle,  (b)  branches  to  the 
molar  and  bicuspid  teeth,  (c)  branches  to  mucous  membrane  and  canine  teeth, 
and  (d)  branches  to  the  integument  of  chin  and  lower  lip. 

The  Gasserian  ganglion  is  sometimes  called  the  semilunar  ganglion.  It 
lies  in  Meckel's  cave  near  the  apex  of  the  petrous  portion  of  the  temporal  bone. 
Beneath  this  ganglion  is  the  motor  root  of  the  fifth  nerve  and  the  large  super- 
ficial petrosal  nerve  which  is  a  branch  of  the  seventh.  This  latter  nerve  helps 
to  form  the  vidian  nerve.  Filaments  from  the  cavernous  plexus  of  the  sympa- 
thetic join   this  ganglion  on   its  inner  side.     Branches  pass  to  the  tentorium 


ANATOMY  IN  A  NUTSHELL. 


403 


cerebelli  and  the  dura  mater  of  the  middle  fossa  from  this  ganglion.  The  three 
great  branches  of  the  fifth  nerve,  viz.,  the  ophthalmic,  the  superior  maxillary, 
and  the  inferior  maxillary  arise  from  this  ganglion. 

Besides  the  Gasserian  ganglion  the  fifth  nerve  has  four  other  ganglia. 
(1)  The  Lenticular,  ciliary,  or  ophthalmic  ganglion,  (Plate  CCXIV)  is  about  the 
size  of  a  pin's  head  and  is  reddish  gray  in  color.  It  is  situated  between  the  optic 
nerve  and  the  External  rectus  muscle.  The  ophthalmic  artery  is  generally  on 
its  inner  side.     This  ganglion  has  three  roots,   (a)  the  sensory  root  which 

PLATE  CCXVII. 


SUPERIOR  NASAL   NERVES 

SPHENOPALATINE  N. 

MECKEL  S  GANGLION 


NASAL    NERVE 
NASAL  BONE 


OTIC  GANGLION 
SYMPATHETIC  ROOT 

AURICULO-TEMPORAL  N. 
MIDDLE  MENINGEAL  A. 


INTERNAL  PTERYGOID 
TENSOR  PALATI 

I 
NASO-PALATINE    N  EXT.  PALATINE     NERVE 

Meckel's  ( Ganglion  and  the  Otic  Ganglion. 

comes  from  the  nasal  branch  of  the  ophthalmic  and  joins  the  upper  angle  of  the 
ganglion.  This  is  the  long  root,  (b)  The  motor  root  which  conies  from  a 
branch  of  the  third  nerve  that  passes  to  the  Inferior  oblique  muscle.  This  is 
the  short  mot  and  joins  the  inferior  angle  of  the  ganglion,  (c)  The  sw,n-\- 
thetic  root  which  coin*  s  from  the  cavernous  plexus  of  the  sympathetic.     It 

usually  blends  with  the  long  root.  This  ganglion  gives  off  five  or  ten  short 
ciliary  nerves  from  the  anterior  superior  and  the  anterior  inferior  angles.  These 
nerves  pass  with  the  ciliary  arteries  forward,  one  set  above  the  optic  nerve  and 


404  ANATOMY  IN  A  NUTSHELL. 

the  other  set  below  it.  After  being  joined  by  the  long  ciliary  nerves  of  the  nasal 
branch  of  the  fifth,  they  pierce  the  back  part  of  the  sclerotic  coat  of  the  eye  and 
then  pass  forward  in  grooves  on  the  inner  surface  of  the  sclerotic  coat  to  supply 
the  ciliary  muscle,  iris,  and  cornea.     (Plate  CCII). 


LESSON  CXIII. 

(2)  Meckel's  ganglion  is  also  called  spheno-palatine  and  is  situated  in  the 
spheno-maxillary  fossa.  It  is  reddish  gray  in  color  and  somewhat  triangular 
in  shape.  It  has  three  roots,  (a)  a  sensory  root  which  comes  from  the  su- 
perior maxillary  nerve  through  the  spheno-palatine  branches.  Most  of  the 
fibers  of  these  nerves  pass  in  front  of  Meckel's  ganglion  but  a  few  of  them  enter 
it.  (b)  Its  motor  root  comes  from  the  facial  nerve  through  the  great  super- 
ficial petrosal,  (c)  Its  sympathetic  root  comes  from  the  great  deep  petrosal 
which  is  a  branch  of  the  carotid  plexus.  This  motor  root  and  this  sensory  root 
unite  to  make  the  vidian  nerve  which  enters  the  posterior  surface  of  the  gang- 
lion. The  great  superficial  petrosal  nerve  comes  from  the  geniculate  ganglion 
of  the  seventh  nerve  in  the  aqueductus  Fallopii.  After  passing  through  the 
hiatus  Fallopii,  it  runs  forward  in  a  groove  on  the  anterior  surface  of  the  petrous 
portion  of  the  temporal  bone  under  the  dura  mater  and  the  Gasserian  ganglion. 
In  the  middle  lacerated  foramen  it  unites  with  the  large  deep  petrosal  which 
comes  from  the  carotid  plexus  and  runs  through  the  carotid  canal  on  the  outer 
side  of  the  internal  carotid  artery.  It  then  enters  the  middle  lacerated  foramen 
where  with  the  large  superficial  petrosal  it  forms  the  vidian.  This  ganglion 
gives  off  the  following  branches,  (a)  ascending  which  are  two  or  three  small 
branches  pass  to  the  orbit  through  the  spheno-maxillary  fissure  and  supply 
its  p<  riosteum,  (b)  the  anterior  palatine,  sometimes  called  large  palatine,  passes 
through  the  posterior  palatine  canal  and  the  posterior  palatine  foramen  to  the 
hard  palate  where  it  runs  forward  in  a  groove  nearly  to  the  incisor  teeth.  It 
supplies  tin-  gums,  mucous  membrane,  and  glands,  and  communicates  with  the 
naso-palatine  nerves.  The  inferior  nasal  branches  come  from  the  anterior 
palatine  and  pass  through  foramina  in  the  palate  bone  and  supply  the  middle 
meatus  and  the  middle  and  inferior  turbinated  bones.  The  anterior 
palatine  also  give  s  off  a  palatine  branch  after  leaving  the  canal  which  supplies 
tin-  .-oil  palate  (c)  the  middle  or  external  palatine  is  not  always  present,  but 
when  it  is  it  passes  through  an  accessory  palatine  canal  to  supply  the  uvula, 
tonsil,  and  soft  palab  ,  (d)  the  posterior  or  small  palatine  passes  through  the 
small  posterior  palatine  canal  to  supply  the  Levator  palati,  Azygos  uvulae,  soft 
palat  .  tonsil,  and  uvula.  These  last  two  branches  with  branches  from  the 
glosso-pharyngeaJ  n<  rve  form  a  plexus  around  the  tonsil.  This  plexus  is  called 
circulus  tonsillaris,  (e)  The  superior  nasal  which  arefour  or  five  branches  pass 
through  the  sph<  no-palatine  foramen  where  they  supply  the  mucous  membrane 
on  tin  superior  turbinated  processes  and  the  middle  turbinated  boms  and  also 
the  mucous  membrane  of  tin  posterior  ethmoidal  cells.  It  communicates  with 
the  anti  rior  dental  by  a  branch  which  passes  to  the  inner  surface  of  the  anterior 
wall  of  the  antrum  of  Highmor<  .     (f)   The  naso-palatine  passes  forward  through 


ANATOMY  IN  A  NUTSHELL.  405 

the  spheno-palatine  foramen  and  then  across  the  roof  of  the  nose  to  the  septum. 
and  from  here  it  runs  downward  and  forward  beneath  the  mucous  membrane 
to  the  anterior  palatine  foramen.  The  naso-palatine  nerve  on  the  left  side 
passes  through  the  anterior  of  the  two  foramina  of  Scarpa,  while  the  one  on  the 
right  side  passes  through  the  posterior  one.  Here  they  supply  the  mucous 
membrane  behind  the  teeth  and  join  the  anterior  palatine  nerve,  (g)  The 
pharyngeal  branches,  called  pterygo-palatine,  arise  from  the  back  of  the  gang- 
lion and  pass  with  the  ptery go-palatine  artery  through  the  ptery go-palatine 
canal  to  supply  the  mucous  membrane  of  the  upper  part  of  the  pharynx  behind 
the  Eustachian  tube,  (h)  The  posterior  superior  nasal  are  a  few  small  branches 
which  pass  in  the  sheath  of  the  vidian  nerve  to  supply  the  mucous  membrane 
at  the  back  part  of  the  roof,  septum,  and  superior  meatus  in  the  nose,  and  also 
to  the  mucous  membrane  covering  the  end  of  the  Eustachian  tube. 

(3)  The  otic  ganalion,  sometimes  called  Arnold's,  is  reddish  gray  in  color. 
It  is  small  and  flat  and  situated  under  the  foramen  ovale  on  the  inner  surface 
of  the  inferior  maxillary  nerve  near  the  point  where  the  motor  and  sensory 
branches  join.  This  ganglion  has  behind  it  the  middle  ni<  ningeal  artery.  On 
its  inner  side  the  cartilaginous  portion  of  the  Eustachian  tube  and  the  origin  of 
the  Tensor  palati  muscle.      This  ganglion  has  three  roots  which  are   (a)   its 

PLATE  CCX VI 11. 


x= 


■"  to  sympathetic 

The  Abdtjcens  or  Sixth  Cranial  Nerve. 

motor  root  which  comes  from  the  internal  pterygoid  branch  of  the  inferior 
maxillary  division  of  the  fifth,  (b)  its  sensory  root  may  come  from  the  same 
origin  as  the  motor  root,  (c)  its  sympathetic  root  comes  from  the  sympathe- 
tic fibers  from  the  middle  meningeal  plexus.  (N.  B.)  Its  motor  root  may 
come  from  the  facial  nerve,  and  its  sensory  from  the  glosso-pharyngeal  nerve 
through  the  small  superficial  petrosal  nerve  and  the  tympanic  plexus. 

Branches  from  this  ganglion  are  (a)  a  filament  passes  backward  on  the 
OUtei  side  of  the  Eustachian  tube  to  the  Tensor  tympani  muscle,  (1>)  a  branch 
passes  to  the  Tensor  palati  muscle.  Both  of  these  branches  are  derived  prin- 
cipally from  the  interna]  pterygoid  nerve,  (<•)  Small  branches  pass  to  the 
chorda  tympani  and  buccal  nerves. 

(4)  The  submaxillary  ganglion  is  situated  above  the  deep  portion  of  the 
submaxillary  gland  close  to  the  posterior  border  of  the  Mylo-hyoid  muscle. 
This  ganglion  has  three  roots  which  are  (a)  its  SYMPATHETIC  ROOT  is  from  the 
plexus  on  the  facial  artery,  (b)  its  motor  root  is  from  the  chorda  tympani  of 
the  facial  and  (c)  its  sensory  root  is  from  the  fifth  nerve.  This  ganglion  gives 
off  the   following   branches,    (a)    five   or  six    small    branches   which   supply    the 


406  ANATOMY  IN  A  NUTSHELL. 

mucous  membrane  of  the  mouth  and  Whorton's  duct  and  the  submaxillary 
gland,  (b)  branches  pass  from  the  lingual  branch  through  the  submaxillary 
ganglion  with  the  chorda  tympani  to  the  sublingual  gland  and  tongue.  Thus 
we  sec  that  each  of  these  four  ganglia  has  three  roots,  a  motor,  a  sensory  and 
a   sympathetic. 


LESSON  CXIV.     (Plate  CCXIX-CCXX.) 

The  superficial  origin  of  the  seventh  nerve  (Plate  CLXXXVII)  is  in  the 
upper  part  of  the  groove  between  the  olivary  and  restiform  bodies  of  the  medulla 
oblongata.  The  deep  origin  is  in  the  pons  under  the  floor  of  the  fourth  ven- 
tricle, anterior  and  external  to  that  of  the  sixth  nerve.  The  seventh  cranial 
nerve  and  the  eighth  cranial  nerve  were  formerly  called  the  seventh  and  con- 
sisted of  two  parts,  portio  dura,  which  is  now  called  the  seventh,  and  the 
portio  mollis,  which  is  now  called  the  eighth.  The  pars  intermedia  arises 
from  the  medulla  between  the  seventh  and  eighth  cranial  nerves  and  is  connected 
with  them  at  its  origin.  The  seventh  nerve  or  facial  nerve  is  the  motor  nerve 
of  the  facial  muscles  of  expression,  of  the  muscles  of  the  external  ear,  Platysma 
myoides,  Buccinator,  posterior  belly  of  the  Digastric,  Stylo-hyoid,  Lingualis, 
and  Stapedius.  This  nerve  passes  with  the  eighth  nerve  into  the  internal  aud- 
itory meatus  where  they  are  joined  by  the  pars  intermedia.  From  the  internal 
auditory  meatus  it  runs  into  the  aqueductus  Fallopii  where  it  has  an  enlarge- 
ment upon  it  called  the  geniculate  ganglion,  which  is  reddish  in  color.  It  now 
bends  backward  on  the  inner  wall  over  the  fenestra  ovalis  and  then  runs  ver- 
tically downward  behind  the  tympanum  to  the  stylo-mastoid  foramen.  After  it 
passes  out  of  the  stylo-mastoid  foramen  it  runs  forward  in  the  parotid  gland  and 
crosses  the  external  carotid  artery.  At  the  ramus  of  the  jaw  it  divides  into  the 
temporo-facial  and  cervico-facial  branches.  These  two  branches  with  their 
sub-divisions  form  the  pes  anserinus. 

The  seventh  nerve  gives  off  the  following  branches  of  communication,  (1) 
in  wditory  canal,  (a)  small  branches  to  the  auditory  nerve,  (2)  in  aqueduct 
of  Fallopius,  (a)  large  superficial  petrosalfrom  thegeniculate  ganglion  which 
with  the  large  deep  petrosal  forms  the  vidian  nerve.  This  nerve  passes  to 
Meckel's  ganglion,  (b)  Small  superficial  petrosal  passes  from  the  geniculate 
ganglion  to  the  otic  ganglion,  (c)  external  superficial  petrosal  from  the  genicu- 
late ganglion  to  the  sympathetic  plexus  around  the  middle  meningeal  artery, 
(d)  a  branch  to  the  auricular  branch  of  the  pneumogastric  (Arnold's).  (3)  At 
tin.  exit  OF  the  stylo-mastoid  foramen  (a)  a  branch  to  the  great  auricular 
of  the  cervical  plexus,  (b)  to  auriculo-temporal  of  the  fifth,  (c)  a  branch  to  the 
pneumogastric,  (d)  a  branch  to  the  glosso-pharyngeal.  (4)  Behind  the  ear, 
a  branch  of  communication  to  the  small  occipital.  (5)  On  the  face, 
branches  to  the  three  divisions  of  the  fifth  nerve.  (6)  In  the  neck,  branches 
to  the  superficial   cervical. 

The  seventh  nerve  has  the  following  branches  of  distribution 

(1)  I.\  the  aqueduct  of  Fallopius,  (a)  tympanic  branch  which  arises 
opposite  the  pyramid  and  passes  through  a  small  canal  in  the  pyramid  to  the 


ANATOMY  IX  A  NUTSHELL. 


407 


Stapedius,  (b)  chorda  tympani  arises  a  quarter  of  an  inch  above  the  stylo-mas- 
toid  foramen  and  passes  upward  and  forward  and  enters  the  tympanum  through 
the  iter  chordae  posterius  on  its  posterior  wall.  This  opening  is  between  the 
opening  of  the  mastoid  cells  and  the  membrana  tympanum.  This  nerve  now 
passes  between  the  handle  of  the  malleus  and  the  vertical  ramus  of  the  incus  to 
the  anterior  inferior  angle  of  the  tympanum  where  it  passes  through  the  iter 
chordae  anterius  (canal  of  Huguier)  at  the  inner  end  of  the  Glasserian  fissure. 

PLATE  CCXIX. 


FROM    GLOSSO-PHARYNGEAl 


SUPERFICIAL    CERVICAL 


Branches  of  Facial  Nerve. 


While  in  the  tympanum  this  nerve  is  covered  with  mucous  membrane.  It 
now  passes  between  the  Pterygoid  muscles  and  after  receiving  a  t\vi<:  from  the 
otic  ganglion  joins  the  lingual  branch  of  the  fifth  nerve  and  passes  with  it  to 
the  submaxillary  ganglion.  The  sublingual  gland  may  receive  a  few  fillers 
from  this  nerve,  but  most  of  them  pass  to  the  Inferior  lingual  muscle.  Sonic 
physiologists  claim  that  the  chorda  tympani  nerve  supplies  the  anterior  two- 
thirds  of  the  tongue  with  taste,  others  claim  thai  the  ninth  nerve  passes  with 
this  chorda  tympani  branch  to  be  distributed  to  the  anterior  two-thirds  of  the 
tongue,  in  such  a  case  the  ninth  nerve  is  the  nerve  of  taste  for  the  entire  tongue. 


408  ANATOMY  IX  A  NUTSHELL. 

(2)  \i:\i;  the  stylo-mastoid  foramex,  (a)  posterior  auricular  arises  from 
the  seventh  nerve  just  outside  the  stylo-mastoid  foramen  and  passes  between  the 
external  auditory  meatus  and  the  mastoid  process  where  it  receives  a  branch 
of  the  auricular  branch  of  the  vaults.  It  communicates  with  the  small  occipital 
nerve  and  the  mastoid  branch  of  the  great  auricular.  It  now  divides  into  an 
auricular  branch  which  supplies  the  Retrahens  aurem  and  an  occipital  branch 
which  supplies  the  Occipitalis  muscle,  (b)  the  digastric  branch  may  have  its 
origin  by  common  trunk  with  the  stylo-hyoid  branch.  It  supplies  the  posterior 
belly  of  the  Digastric  and  after  perforating  that  muscle  joins  the  glossopharyn- 
geal nerve,  (c)  stylo-hyoid  branch  enters  the  Stylo-hyoid  muscle  near  its  center 
ami  communicates  with  the  sympathetic  plexus  on  the  external  carotid  artery. 
:;>  On  the  FACE,(a)it  has  the  temporo-facial  branch  which  passes  through 
the  parotid  gland  over  the  external  carotid  artery  and  temporo-maxillary  vein, 
and  as  it  passes  over  the  condyle  of  the  lower  jaw  it  communicates  with  the 
auriculo-temporal  branch  of  the  fifth  nerve,  it  finally  divides  into  three  sets 
of  branches,  first,  temporal  branch  which  crosses  the  zygoma  of  the  temporal 
bone  and  supplies  the  Attrahens aurem  and  Attolens  aurem  muscles  and  joins 
with  the  temporal  branch  of  the  temporo-malar  of  the  fifth  ami  the  auriculo- 
temporal also  of  the  fifth.  It  supplies  the  Orbicularis  palpebrarum,  Corrugator 
supercilii, and  the  Frontalis  muscles,  and  joins  the  supraorbital  and  lachrymal 
blanches  of  the  ophthalmic  division  of  the  fifth;  second,  the  malar  branches  pass 
to  the  outer  portion  of  the  orbit  where  a  few  fibers  pass  to  the  Orbicularis  pal- 
pebrarum arid  join  branches  from  the  lachrymal  nerve,  and  the  others  supply 
the  lower  eye  lid  and  join  the  malar  branch  of  the  superior  maxillary;  third,  the 
infraorbital  passes  to  the  parts  between  the  mouth  and  the  orbit  and  supplies 
the  superficial  facial  muscles  and  the  Pyramidalis  nasi  ami  joins  with  the  in- 
fratrochlear  and  nasal  branches  of  the  ophthalmic  at  the  inner  angle  of  the  orbit. 
Other  branches  pass  under  the  Zygomatici  and  the  Levator  labii  superioris, 
supplying  both  of  these  muscles  as  well  as  the  Levator  anguli  oris.  They  form 
an  infraorbital  plexus  with  the  infraorbital  branch  of  the  superior  maxillary  and 
buccal  branches  of  the  cervical  facial  nerves.  These  branches  supply  the  Leva- 
tor labii  superioris  alanine  nasi  and  the  muscles  of  the  nose,  (b)  The  cervical 
facial  branch  passes  forward  through  the  parotid  gland  across  the  external 
carotid  artery  and  receives  branches  from  the  great  auricular.  It  divides  op- 
posite the  angle  of  the  lower  jaw  into  three  sets  of  branches,  first,  buccal  which 
crosses  the  Masseter  muscle  to  supply  the  Buccinator  and  the  Orbicularis  oris. 
These  buccal  branches  join  the  infraorbital  branches  of  the  temporo-facial  and 
the  buccal  branches  of  the  inferior  maxillary;  second,  the  supramaxillary  (man- 
dibular) branches  pas>  under  the  Platysma  myoides  and  Depressor  anguli  oris 
to  supply  the  muscle  of  the  chin  and  lower  lip  and  join  the  mental  branch  of  the 
inferior  dental  of  the  fifth:  third,  the  inframaxillary  (cervical)  branches  pass 
under  the  Platysma  myoides  and  supply  it.  One  branch  descends  vertically 
to  join  the  superficial  cervical  of  the  cervical  plexus. 

The  eighth  nerve  will  be  given  with  the  anatomy  of  the  ear. 


PLATE  CCXX. 


TERMINATIONS  OF 
SUPRATROCH  LEAR 


OF     INFRA  TROCHLEAR 


OF     INFRA-ORBITAL 


Showing  Facial  Nerve  \\i»  Superfic]  \i.  Cki;\  ecal  Plexuj 

109 


410  ANATOMY  IN  A  NUTSHELL. 


LESSON  CXV. 

The  ninth  cranial  nerve  called  the  glosso-pharyngeal  passes  to  the  tongue 
and  the  pharynx.  It  supplies  the  raucous  membrane  of  the  pharynx,  tonsil, 
and  fauces  with  ordinary  sensation,  and  the  tongue  it  supplies  with  a  nerve  of 
taste.  This  nerve  is  a  compound  nerve.  Its  superficial  origin  is  in  the 
groove  between  the  olivary  and  restiform  bodies.  (Plate  CLXXXVII).  Its 
DEEP  ORIGIN  is  from  the  lower  part  of  the  floor  of  the  fourth  ventricle  from  three 
main  points.  (1)  from  a  nucleus  of  gray  matter  beneath  the  inferior  fovea, (2) 
from  the  funiculus  solitarius,  (3)  from  the  nucleus  ambiguus.  The  nucleus 
ambiguus  gives  motor  branches  to  the  glosso-pharyngeal  and  the  tenth  nerves 
and  to  the  bulbar  part  of  the  spinal  accessory  nerve.  The  sensory  fibers  of  the 
ninth  nerve  are  in  the  jugular  and  petrosal  ganglia.  Van  Gehuchten  says  that 
the  fasciculus  solitarius  is  the  only  sensory  nucleus  of  this  nerve.  The  ninth 
nerve  passes  from  its  superficial  origin  outward  to  leave  the  skull  through  the 
centra]  part  of  the  jugular  foramen.  It  has  a  sheath  of  dura  mater  of  its  own 
and  is  situated  external  to  and  in  front  of  the  pneumogastric  and  spinal  acces- 
sory nerves.  It  descends  in  front  of  the  internal  carotid  artery  and  beneath 
the  styloid  process  and  muscles  attached  to  it  to  the  lower  border  of  the  Stylo? 
pharyngeus  muscle.  The  nerve  now  passes  inward,  lying  upon  the  Stylo- 
pharyngeus  and  the  Middle  constrictor  of  the  pharynx.  It  finally  passes  be- 
neath the  Hyo-glossus  muscle  to  its  destination.  This  nerve  has  two  ganglia 
upon  it .  The  jugular  ganglion  or  superior  one  is  in  the  upper  part  of  the  groove 
in  which  the  nerve  is  placed  while  passing  through  the  jugular  formen.  It  is 
quite  smal]  and  may  be  regarded  as  a  segmentation  of  the  lower  ganglion.  The 
petrous  ganglion  is  the  inferior  one  and  is  situated  in  the  lower  border  of  the 
petrous  portion  of  the  temporal  bone.  It  is  much  larger  than  the  superior  one. 
Fibers  arise  from  it  to  connect  this  nerve  with  the  tenth  and  the  sympathetic. 
It  sends  two  filaments  to  the  pneumogastric,  one  of  which  passes  to  the  auricu- 
lar branch  of  the  pneumogastric,  and  the  other  to  the  ganglion  of  the  root  of 
the  tenth.  The  branch  which  passes  to  the  sympathetic  passes  to  the  superior 
cervical  ganglion,  and  the  branch  which  passes  to  the  facial  nerve  arises  from 
the  nerve  below  the  petrous  ganglion  and  joins  the  facial  just  after  it  leaves  the 
stylo-mastoid   foramen.     (Plate  CCXXII). 

It-  branches  of  distribution  are,  (1)  tympanic  branch,  called  Jacobson's 
nerve,  comes  from  the  petrous  ganglion  and  passes  in  a  small  canal  in  the  lower 
surface  of  the  petrous  portion  of  the  temporal  bone.  The  lower  opening  of  this 
canal  is  on  a  ridge  between  the  carotid  canal  and  the  jugular  fossa.  This  nerve 
now  passes  to  the  tympanum  and  forms  the  typmanic  plexus.  This  plexus 
gives  off  (a  I  a  greater  pari  of  the  small  superficial  petrosal,  (b)  a  branch  to  the 
large  superficial  petrosal,  (c)  branches  to  the  tympanic  cavity,  (d)  branches  to 
the  carotid  plexus,(e)  to  the  Eustachian  tube,  (f)  to  fenestra  ovalis,  (g)  to  fen- 
estra rotunda. 

(2)  Pharyngeal  branches  which  are  three  or  four  in  number  unite  with 
the  pharyngeal  branches  of  the  pneumogastric  and  sympathetic  nerves  to  form 


ANATOMY  IN  A  NUTSHELL. 


411 


the  pharyngeal  plexus.  This  union  takes  place  opposite  the  Middle  constrictor 
of  the  pharynx.  Branches  from  this  plexus  perforate  the  muscular  coat  of  the 
pharynx  to  supply  the  muscles  and  the  mucous  membrane. 

(3)  Muscular  branch  which  is  distributed  to  the  Stylo-pharyngeus  mus- 
cle, receives  a  communication  from  the  seventh  nerve. 

(4)  The  tonsillar  branches,  which  are  small,  arise  undercover  of  the 
Hyo-glossus  muscle.  They  pass  to  the  tonsil  around  which  they  form  a  plexus, 
circulus  tonsillaris.  From  this  plexus  twigs  pass  to  the  pillars  of  the  fauces  and 
to  the  soft  palate  where  they  communicate  with  the  palatine  nerve. 

PLATE  CCXXI. 


STEP'.     V 


LOCUS    PERFORATES'   / 
POSTICUS  .  // 


M'ODLE  PEDUNCLE 

OP 
THE    CEREBELLUM 
RESTIFORM     BODY 

OLIVARY     BODY 

=  •=:•,■  - 

ANTERIOR     SUPERFICIAL 
ARCUATE  FIBERS 

DECUSSATION  OF 


OPTIC  NERVE 
INFUNDIBULUM 

TUBER     CINEREUM 
CORPORA  VAMMILLARIA 

0CUL0-M0T0R      III.' 

TROCHLEAR  NERVE    IV.     WINDING  ROUND  THE  CRUS  CEREBRI 


TRIGEMINAL  NERVE   V 

ABDUCENT  NERVE   VI.) 

FACIAL  NERVE    VII. 


SUPERIOR     SEMICIRCULAR       CANAL 

EXTERNAL  SEMICIRCULAR       CANAL 


POSTERIOR  SEMICIRCULAR  CANAL 

Origin  and  Distribution  of  Auditory  Nerve. 

(5)  The  lingual  nerves  are  two  in  number,  one  supplies  the  circumval- 
late  papillae  and  mucous  membrane  of  the  base  of  the  tongue,  and  the  other  sel 
supplies  the  mucous  membrane  and  follicular  glands  and  the  posterior  one-halt 
of  thegtongue  and  communicates  with  the  Lingua]  nerve. 


LESSON  CXVI. 

The  tenth  cranial  nerve,   pneumogastric,  or  vagus.     Pancoasl    rails    this 
nerve    the     auriculo-laiyngo-pharyngo-03sophago-tracheo-pulmono-cardio-gas- 

tro-hepatic.     This  is  a  compound  nerve  and  sends  motor  and  sensory  fibers 
the  organs  of  voice  and  respiration,  and  motor  fiber*  to  the  pharynx,  the  oesopha- 


412  ANATOMY  IN  A  NUTSHELL. 

mis.  stomach,  and  heart.  It  is  the  longest  of  all  the  cranial  nerves.  Its  super- 
ficial  origin  is  from  the  groove  between  the  olivary  and  restiform  bodies  below 
that  <>f  the  glosso-pharyngeal  nerve  by  eight  or  ten  fasciculi  (Plate  CLXXXVII). 
Its  deep  origin  is  in  the  floor  of  the  fourth  ventricle  from  the  nucleus  vagi 
beneath  the  ala  cinerea  below  ami  continuous  with  the  nucleus  of  origin  of  the 
glosso-pharyngeal.  The  origin  of  the  sensory  fibers  of  the  tenth  nerve  is  in  the 
ganglion  of  the  root  and  the  ganglion  of  the  trunk.  Van  Gehuchten  says  that 
the  only  sensory  nucleus  of  the  tenth  is  in  the  fasciculus  solitarius.  The  nerve 
now  passes  over  the  flocculus  to  the  middle  compartment  of  the  jugular  fora- 
men, passing  behind  the  glosso-pharyngeal  in  the  same  sheath  with  the  spinal 
accessory.  After  leaving  the  jugular  foramen  it  is  connected  with  the  accessory 
part  of  the  spinal  accessory  and  has  an  enlargement  called  the  ganglion  of  the 
trunk.  The  accessory  part  of  the  spinal  accessory  nerve  sends  most  of  its  branches 
into  the  pharyngeal  and  superior  laryngeal  branches  of  the  tenth,  while  some  of 
its  fibers  join  the  ganglion  of  the  trunk.  The  tenth  nerve  now  passes  down  the 
neck  in  the  carotid  sheath  to  the  root  of  the  neck.  This  sheath  contains  the  in- 
terna] jugular  vein  externally,  the  common  carotid  artery  internally,  and  the 
tenth  nerve  between  them  but  on  a  plane  posterior.     The  relations  of  this 

SHEATH    ARE    AS    FOLLOWS: 

Ix  Front. — A  few  filaments  descending  from  the  loop  of  communication 
between  the  descendens  and  communicans  hypoglossi. 

Behind. — (1)  The  inferior  thyroid  artery,  (2)  The  recurrent  laryngeal 
nerve.  (3)   The  sympathetic  nerve. 

On  the  inner  side. — (1)  Trachea,  (2)  Thyroid  gland,  (3)  Lower  part  of 
the  larynx  (more  prominent  in  the  female). 

The  ganglion  of  the  root  is  a  small  gray  mass  about  five  millimetres  in 
diameter  and  is  situated  in  the  jugular  foramen.  It  is  connected  with  the 
superior  cervical  ganglion  of  the  sympathetic  and  the  spinal  accessory  nerves. 
It  gives  off  an  auricular  branch  by  which  it  is  connected  with  the  facial  and  the 
glosso-pharyngeal  nerves.     It  also  gives  off  a  recurrent  meningeal  branch. 

The  ganglion  of  the  trunk  is  below  the  base  of  the  skull  and  in  front  of  the 
internal  jugular  vein  and  is  about  seventeen  millimetres  long.  It  is  connected 
with  the  accessory  part  of  the  spinal  accessory  nerve,  with  the  hypoglossal  nerve, 
ami  with  the  superior  cervical  ganglion  of  the  sympathetic,  and  with  the  loop 
between  the  firsl  and  second  cervical  nerves.  The  branches  it  gives  off  are  (1) 
a  pharyngeal,  (2)  a  superior  laryngeal,  (3)  a  superior  cardiac  (Plates  CCXXII- 
(  (XX  I II. 

The  right  pneuinogastric  nerve  passes  downward  between  the  first  part  of 
the  subclavian  artery  and  the  subclavian  vein  beside  the  trachea,  behind  the 
righl  innominate  vein,  and  behind  the  root  of  the  right  lung.  It  helps  to  form 
the  posterior  pulmonary  plexus.  It  now  passes  downward  in  two  cords  which 
run  on  the  oesophagus  and  communicate  with  the  pneumogastric  nerve  of  the 
opposite  side  making  the  oesophageal  plexus.  The  two  divisions  of  the 
pneumogastric  nerve  mute  into  one  trunk  behind  the  (esophagus  and  passing 
through  the  oesophageal  opening  in  the  Diaphragm,  is  distributed  to  the  pos- 
terior surface  ot'  the  stomach  and  to  the  solar  plexus  and  its  divisions. 


PLATE  CCXXII.       > 


M**^^ 


Showing  Disthibution  of  Ninth,  Tenth,  and  Eleventh  Cranial  Nehves. 

413 

(Mi'litied   from  Gray's  Flower.) 


414  ANATOMY  IN  A  NUTSHELL. 

The  left  pneumogastric  nerve  passes  between  the  subclavian  artery  and  the 
carotid  artery,  behind  the  left  innominate  vein.  At  this  point  the  left  phrenic 
nerve  crosses  it.  It  now  passes  in  front  of  the  arch  of  the  aorta  behind  the  root 
of  the  left  lung  where  it  helps  to  form  the  posterior  pulmonary  plexus.  It  now 
passes  along  the  anterior  surface  of  the  oesophagus  through  the  Diaphragm  to 
be  distributed  to  the  anterior  surface  of  the  stomach  and  the  liver.  It  occasion- 
ally joins  the  solar  plexus. 

The  pneumogastric  nerve  has  the  following  connections: 

(1)  Thk  ganglion  of  the  root  is  joined  to  the  spinal  accessory,  (2)  to  the 
petrous  ganglion  of  the  glosso-pharyngeal,  (3)  to  the  sympathetic.  The  gang- 
lion of  thk  trunk  is  joined  (1)  to  the  hypoglossal,  (2)  to  the  sympathetic,  (3) 
to  a  loop  between  the  first  and  second  cervical  nerves. 

The  branches  of  distribution  are  (1)  meningeal  branch  (recurrent)  which 
is  a  small  filament  given  off  from  the  ganglion  of  the  root  in  the  jugular  foramen. 
Ii  is  distributed  to  the  dura  mater  in  the  posterior  fossa  at  the  base  of  the  skull. 
(2)  The  auricular  branch  (Arnold's)  comes  from  the  ganglion  of  the  root  in 
the  jugular  foramen.  A  branch  from  the  petrous  ganglion  of  the  glosso-pharyn- 
geal joins  it.  The  nerve  now  passes  through  a  foramen  in  the  outer  wall  of  the 
jugular  fossa  of  the  petrous  portion  of  the  temporal  bone  and  communicates 
with  the  facial  nerve.  It  leaves  the  temporal  bone  by  the  stylo-mastoid  fora- 
men as  a  rule  but  it  may  pass  through  the  tympano-mastoid  fissure.  Behind 
the  pinna  it  divides  into  two  branches  one  of  which  joins  the  posterior  auricu- 
lar of  the  facial,  while  the  other  supplies  the  posterior  and  inferior  part  of  the 
externa]  auditory  meatus  and  the  back  of  the  pinna.  (3)  Pharyngeal 
p.i;  \  \<  ihes  are  t  wo  or  three  and  join  the  pharyngeal  branch  of  the  glosso-pharyn- 
geal on  the  outer  surface  of  the  internal  carotid  artery  and  after  passing  with  this 
artery  interna]  to  the  external  carotid  artery,  it  turns  downward  and  inward  to 
reach  the  posterior  aspect  of  the  pharynx.  At  this  point  the  two  nerves  are 
joined  by  branches  from  the  superior  cervical  ganglion  of  the  sympathetic  to 
help  form  the  pharyngeal  plexus.  This  nerve  is  the  principal  motor  nerve  of  the 
pharynx  and  comes  from  the  upper  part  of  the  ganglion  of  the  trunk  of  the 
pneumogastric.  .Most  of  its  fibers  come  from  the  accessory  portion  of  the 
spinal  accessory  nerve.  (4)  The  superior  laryngeal  nerve  comes  from  the 
ganglion  ^^  the  Punk  and  passes  behind  the  internal  carotid  artery  where  it 
divides  into  the  external  laryngeal  nerve  which  branch  joins  the  pharyngeal 
plexus  and  the  sympathetic,  and  it  supplies  the  Crico-thyroid  muscle  and  In- 
ferior constrictor  muscle  and  occasionally  the  thyroid  gland;  and  the  internal 
laryngeal  nerve  which  passes  through  the  thyro-hyoid  membrane  to  be  distri- 
buted to  the  mucous  membrane  of  the  larynx,  and  it  joins  a  branch  from  the 
recurrenl  laryngeal,  (5)  The  inferior  oe  recurrent  laryngeal  nerve  on 
the  right  side  arises  at  the  root  of  the  nick  in  front  of  the  first  portion  of  the 
right  subclavian  artery.  It  passes  around  the  artery  and  runs  upward  and 
and  slightly  inward  behind  the  common  carotid  artery.  It  now  runs  in  a  groove 
between  the  common  carotid  artery  and  the  (esophagus,  having  with  it  branches 
of  the  inferior  thyroid  artery.  It  passes  under  the  lower  border  of  the  Inferior 
constrictor  of  the  pharynx  into  the  larynx  where  it  breaks  up  into  branches  for 


PLATE  CCXXIII. 


LINGUAL  NERVE 

PHARYNGEAL   BR 
OF  PNEUMOGASTRlC 
<=HB  MAXILLARY 

GANGLION 


HYPOGLOSSAL    NERVE 


SUPERIOR    LARYNGEAL    N 

EXTERNAL    LARYNGEAL  NERVE 
PHARYNGEAL    PLEXUS 
MIDDLE     CONSTRICTOR 


INFERIOR     CARDIAC 

PNEUMOGASTRlC 

LEFT     COMMON     CAROTID 

PHRENIC 


RECURRENT  LARYNGEAL  NERVE 
PULMONARY  PLEXUS 


SPINAL  ACCESSORY 
GANGLION     OF       PNEUMOGASTRlC 

SUPERIOR  CERVICAL  GANGLION 


SECOND   CERVICAL  NERVE 
STEfiNO-MASTOID 
THIRD       CERVICAL  NERVE 


MIDDLE  CERVICAL  GANGLION 

SPINAL  ACCESSORY 
^M. SUBCLAVIAN  ARTERY 

BRACHIAL     PLEXUS 
|NFER'"R  CERVICAL  GANGLION 
TRAPEZIUS 


VENAAZYGOS    TERTIUS 


INTEKCOSTAI    VEI* 
ARTERY 
IERVE 


NA  AZYGOS     MINOB 


Showing  Pneumogastric  Nerve  and  Sympathetic  Ganglia. 


416  ANATOMY  IN  A  NUTSHELL. 

all  the  intrinsic  muscles  of  the  larynx  except  the  Crico-thyroid  muscle  and 
communicates  with  the  superior  laryngeal.  Near  the  beginning  of  this  nerve 
it  usually  gives  off  a  cardiac  branch.  Between  the  (esophagus  and  the  trachea 
it  gives  branches  to  these  structures  and  near  its  termination  it  gives  some 
branch)  s  to  the  Inferior  constrictor  muscle.  On  the  left  side  the  recurrent  laryn- 
geal nerve  conn  s  in  front  of  the  arch  of  the  aorta  and  winds  round  the  arch  ex- 
ternal to  the  obliterated  ductus  arteriosus  and  passes  up  the  left  side  of  the 
trachea.  The  remainder  of  its  course  is  similar  to  that  of  the  right  side.  This 
nerve  passes  through  the  superior  opening  of  the  thorax  while  the  right  one  does 
not.  (6)  The  cardiac  brahches  of  the  pneumogastric  all  pass  to  the  deep 
cardiac  plexus  except  the  inferior  cervical  cardiac  on  the  left  side.  It  gives  off 
three  cardiac  branches,  (a)  the  superior  cervical  arises  from  the  pneumogastric 
from  the  upper  part  of  the  neck  and  join  the  corresponding  branches  from  the 
sympathetic,  (b)  the  inferior  cervical  cardiac  nerve  of  the  left  side  passes  down- 
war*  1  on  the  1(  f1  side  of  the  arch  of  the  aorta  between  this  arch  and  the  pleura 
and  joins  the  superficial  cardiac  plexus.  The  phrenic  nerve  is  in  front  of  it  and 
the  left  superior  cardiac  of  the  sympathetic  is  behind  it  as  it  crosses  the  arch  of 
the  aorta.  On  the  right  side  this  branch  passes  in  front  or  beside  the  innomi- 
nate artery  on  the  side  of  the  trachea  to  join  the  deep  cardiac  plexus,  (c)  Tho- 
racic cardiac  branches  arise'  near  the  recurrent  laryngeal  nerve  and  the  one  on 
the  right  side'  is  on  a  higher  level  than  the  one  em  the  left  because  the  recurrent 
laryng<  al  n<  rve  com<  s  off  em  a  higher  level  on  the  right  side.  They  pass  inward 
to  the  fronl  of  the  lower  end  of  the  trachea  to  end  in  the  deep  cardiac  plexus. 

7  i  The  anterior  pulmonary  branches  are  two  or  three  in  number  which 
arise  at  the  upper  border  at  the  root  of  the  lung.  They  join  filaments  from  the 
sympathetic  and  form  the'  anterior  pulmonary  plexus  from  which  fine  branches 
pass  along  the  branches  into  the  lung.  (8)  The  posterior  pulmonary 
br  inches  are'  larger  than  the  anterior  branches  anel  are  joined  by  filaments  from 
the  third  and  fourth  thoracic  ganglia  of  the'  sympathetic  and  form  the  posterie>r 
pulmonary  plexus  from  which  branche  s  pass  into  the-  root  of  the  lung.  Occasion- 
ally branches  from  the  first  and  second  thoracic  ganglia  pass  te>  this  plexus. (9) 
Oesophageal  branches  are  given  off  from  the-  pneumogastric  both  above  and 
below  the  pulmonary  branches,  but  the'  low*  r  one  s  are-  larger  and  more  numerous 
than  the'  upper  ones.  These  oesophageal  branches,  with  the'  corresponding 
branch*  s  of  the  opp<  sit<  side,  form  the  oesophageal  plexus  (Gulae  plexus).  (10) 
The  gastric  branches  pass  through  the  oesophageal  op<  ning  in  the  Diaphragm 
and  the  1  <  ft  one  is  distributed  to  the  anterior  surface  of  the  stomach.  Some 
of  the  largest  branch*  -  accompany  the  gastric  artery  along  the  lesser  curvature 
of  the'  stomach,  and  from  these  small  twigs  pass  on  the'  hepatic  artery  and  join 
the  hepatic  plexus.  The  terminal  branches  of  the  right  pneumogastric  are 
distributed  on  the  posterior  surface  of  the  stomach  and  join  the  cceliac  plexus, 
splenic  plexus,  and  the  1<  ft  r<  mil  plexus. 


LESSON  CXVII. 

The  eleventh  cranial  ner\e  (Plate  CLXXXVII)  is  called  the'  spinal  acccs- 
SOry  and  is  purely  motor.  It  consists  of  two  main  parts.  (1)  an  ACCESSORY  or 
MEDULLARY    PORTION,    and    (2)     \    SPINAL    PORTION.        THE   SUPERFICIAL     ORIGIN 


li 


ANATOMY    IN    A    NUTSHELL.  417 

of  this  nerve  is  by  four  or  five  small  filaments  from  the  sides  of  the  medulla  just 
below  the  superficial  origin  of  the  tenth  nerve.  Its  deep  origin  is  in  the  floor 
of  the  fourth  ventricle  in  a  gray  nucleus  at  the  back  of  the  medulla,  dorso- 
lateral to  the  hypoglossal  nucleus.  The  superficial  ami  deep  origin  just  given 
are  those  of  the  accessory  portion  of  the  nerve.  Tin-:  superfk  i  \i.  origin  of  the 
spinal  portion  is  from  the  lateral  tract  of  the  cord  as  low  down  as  the  sixth  cer- 
vical nerve.  The  deep  origin  of  the  spinal  portion  may  be  traced  to  the 
medio-lateral  tract  of  the  gray  matter  of  the  cord.  This  spinal  portion  of  the 
nerve  passes  upward  between  tin  ligamentum  denticulatum  ami  the  posterior 
roots  of  the  spinal  nerves  to  enter  the  skull  through  the  foramen  magnum.  It 
is  then  directed  outward  to  the  jugular  foramen  where  it  passes  through  the 
middle  compartment  of  this  foramen  in  a  common  sheath  with  the  pneumogas- 
tric  but  separated  from  it  by  a  fold  of  arachnoid.  While  in  the  cranium  it  in- 
n  -changes  fibers  with  the  accessory  portion.     After  passing  out  of  the  foramen 

PLATE  CCXXIV. 


SUPERIOR  DIVISION  OF     ,RD. 

'W/Ji    / 

NASAL        ' 


INFERIOR    DIVISION    OF      RD. 
TH. 
OPHTHALMIC  VEIN 

OPTIC     FORAMEN 


Showing  Structurks  Passing  Through  the  Sphenoidal  Fissure. 

in.-  gnum,  it  passes  downward  behind  the  Digastric  and  Stylo-hyoid  muscles  to 
the  upper  part  of  the  Sterno-cleido-mastoid.  It  supplies  the  Sterno-cleido- 
oid  and  crosses  the  post(  rior  triangle  of  the  neck  to  the  d<  ep  surface  of  the 
Trapezius.  The  accessory  portion,  while  in  the  jugular  foramen,  is  connected 
to  the  ganglion  of  the  root  of  the  pn<  umogastric,  and  sonic  of  its  fib<  rs  become 
B<  parated  from  the  spinal  portion  and  pass  to  the  ganglion  of  the  trunk  of  the 
pneumogastric  from  which  they  p;>ss  to  the  pharyngeal  and  superior  laryngeal 
branches  of  the  pneumogastric.  It  supplies  the  muscles  of  the  soft  palate 
through  the  pharyngeal  branch.  Some  of  the  branches  are  continue. I  below 
die  ganglioD  of  the  trunk  of  the  pn<  umogastric  into  the  recurrent  laryng<  ;i!  ami 
cardiac  nerves.      This  is  the  nerve  that  is  affect  ed  in  spasmodic  torticollis.    (Plate 

CCXXII). 


LESSON  ('Will. 
The  twelfth  cranial  nerve  or  hypoglossal  is  exclusively  motor  and  supplies 

the  intrinsic  muscles  of  the  tongue  and  the  Genio-hyoid  muscle  and  all  the  ex- 
trinsic muscles  of  the  tongue  e\c<  pt  the  PalatO-gloSSUS.  'I'm  SUPERFICIAL 
ORIGIN  of  this  nerve  arises  by  tell  or  fifteen  filaments  between  the  pyramidal  and 


118  ANATOMY    IN    A    NUTSHELL. 

olivary  bodies  of  the  medulla.  (Plate  CLXXXVII).  Its  deep  origin  is  from 
the  trigonum  hypoglossi  in  the  floor  of  the  fourth  ventricle.  The  nerve  passes 
in  two  bundles  through  the  anterior  condyloid  foramen  after  which  they  unite. 
It  now  passes  downward  hot  ween  the  tenth  and  eleventh  nerves  and  between  the 
internal  carotid  artery  and  the  internal  jugular  vein  to  the  lower  border  of  the 
Digastric  muscle.  It  now  curves  round  the  occipital  artery  crossing  the  ex- 
ternal carotid  and  lingual  arteries  to  pass  between  the  Mylo-hyoid  and  Hyo- 
glossus  muscle.  It  now  enters  the  Genio-hyo-glossus  muscle  and  is  continued 
forward  to  the  tip  of  the  tongue.  Its  branches  of  communication  are  (1)  with 
the  GANGLION  OF  the  trunk  of  the  pneumogastric,  which  connection  takes 
place  close  to  the  exit  of  the  nerve  from  the  skull.  It  also  communicates  with 
ilu  pharyngeal  plexus  as  it  winds  around  the  occipital  artery.  (2)  It  commu- 
nicates with  Tin;  SUPERIOR  CERVICAL  GANGLION  of  the  sympathetic  which 
communication  takes  place  opposite  the  atlas.     (3)   It  communicates     with 

TIIK   KIKST   AND  SECOND  CERVICAL  NERVES.       (4)    WlTH  THE  LINGUAL  BRANCH  OF 

Tin;  fifth  which  communication  takes  place  near  the  anterior  border  of  the 
Hyo-glossus  muscle.     (Plate  CCXXII). 

1 1>  branches  of  distribution  are  (1)  meningeal,  which  are  represented  by 
two  filaments  given  off  in  the  anterior  condyloid  foramen,  pass  backward  into 
the  posterior  fossa  of  the  skull  te>  be  distributed  to  the  dura  mater.  These 
nerves  are'  probably  derived  from  the  first  and  second  cervical  nerves,  the  sym- 
pathetic, or  the  tenth.  It  was  formerly  thought  they  were'  derived  from  the 
fifth,  (2)  Descendens  hypoglossi  is  given  off  from  the  twelfth  nerve  as  it 
passes  round  the  occipital  artery.  From  this  point. is  passes  down  over  the 
-heath  of  the'  common  carotid  artery  and  joins  the'  conmmnicans  hypoglossi 
from  the  second  and  third  cervical  nerves  just  above  the  middle  of  the  Omo- 
hyoid muscle.  This  loop  between  the  descendens  hypoglossi  anel  communicans 
hpyoglossi  is  called  the'  ansa  hypoglossi.  From  this  ansa  branches  are  given  to 
the  Sterno-hyoid,  Sterno-thyroid,  and  the  posterior  belly  of  the  Orno-hyoid 
muscles.  A  filament  from  this  loop  descends  into  the  chest  to  join  the  cardiac 
and  phrenic  nerves.  (3)  The  thyro-hyoid  branch  passes  from  the  twelfth 
nerve  near  the-  posterior  border  of  the  Hyo-glossus  muscle  downward  to  supply 
the  Thyro-hyoid  muscle.  (4)  Muscular  branches  are  distributed  to  the 
following  muscle's,  (a)  Stylo-glossus,  (b)  Hyo-glossus,  (c)  Genio-hyoid,  (d) 
Genio-hyo-glossus,  (e)  to  the  intrinsic  muscles  of  the  tongue.  Possibly  the  In- 
ferior lingual  muscle  receives  the  chorda  tympani  branch  of  the  seventh. 


Sympathetic  System. 
LESS<  >.\  (XIX.  (  Plate's  ( !XCV-(  !X(  !VI-(  !XCV  1 1-(  !XCV I II.) 
The  sympathetic  nerve  differs  from  the  somatic  nerve  in  four  different 
ways:  (1)  it  has  a  greal  tendency  to  form  plexuses;  (2)  it  has  a  preponder- 
ance of  Qon-medullated  fibres;  (3)  fibers  are'  interrupted  in  nerve  cells  and  (4) 
its  individual  nerve  fibers  are  smaller.  The  sympathetic  nerve  is  the  nerve  of 
organic  life.  If  we  had  nothing  but  the'  sympathetic  nerve'  it  would  be  in  the 
form  of  the  human  body.  lis  frame  work  consists  of  a  chain  of  ganglia  extend- 
ing in  fnmt  of  the-  vertebral  column,  the  upper  ganglia  being  on  the  anterior 


PLATE  CCXXV 


Showing  the  Ajbdomin  \i.  Aim:  \-. 
419 


420  ANATOMY    IN    A    NUTSHELL. 

communicating  artery  of  the  circle  of  Willis  and  is  called  the  ganglion  of  Ribes; 
the  Lower  one,  the  ganglion  of  impar  is  in  front  of  the  coccyx.  This  frame  work 
mighl  be  compared  to  a  chain  of  beads.  The  thread  upon  which  tho  beads  are 
strung  is  called  the  sympathetic  nerve  and  the  beads  represent  the  ganglia.  In 
the  cervical  region  there  are  only  three,  in  the  dorsal  region  eleven  or  twelve, 
in  the  lumbar  region  four,  and  in  the  sacral  region  five.  There  ought  to  be 
thirty-one  of  these,  one  for  each  spinal  nerve,  but  on  account  of  the  coalesecence 
of  several  into  one,  there  are  only  twenty-three. 

There  is  only  one  nervous  system  but  it  has  three  divisions:  (1)  the  cen- 
tral consisting  of  the  brain  and  spinal  cord;  (2)  the  twelve  cranial  nerves  and 
the  thirty-one  spinal  nerves  is  the  peripheral  system;  and  (3)  the  rest  is  called 
i  lie  sympathetic  system.  The  frame  work  of  the  sympathetic  is  connected  to 
the  anterior  branch  of  the  spinal  nerves  by  rami  communicantes.  Each  gang- 
Lion  giv< -s  off  a  ramus  to  the  anterior  branch  of  the  spinal  nerve  which  is  graj  , 
and  the  anterior  branches  of  the  spinal  nerves  in  the  dorsal  and  lumbar  regions 
give  off  rami  communicantes,  which  are  white,  to  the  ganglion  of  the  syntpa- 
th<  tic.  Gray  rami  communicantes  are  indigenous  to  every  part  of  the  spinal 
cord,  while  the  white  are  indigenous  to  the  dorsal  and  lumbar  regions.  Every 
branch  that  leaves  a  ganglion  is  called  a  ramus  efferent, and  these  rami  efh  ren- 
tes have  special  names,  for  instance,  those  going  to  anterior  branches  of  the 
first  four  cervical  nerves  are  called  rami  communicantes  and  those  that  leave 
1 1  it  se  ganglia  and  go  to  the  heart  are  called  cardiac  branches.  The  gray  rami 
communicantes  after  theypass  to  the  anterior  branch  of  the  spinal  nerves  fol- 
low these-  nerves  to  their  destination.  Those  that  are  given  off  to  bone,  facia, 
Ligament,  or  blood  vessels  are  called  gray  rami  communicantes,  for  instance, 
the  musculo-cutaneous  nerve-  of  the  brachial  plexus  gives  off  a  branch  that  goes 
into  the  nutrie  nt  foramen  of  the-  humerus;  this  is  an  <  xample  of  the  gray  rami 
communicantes.  Tin-  anterior  crural  nerve  and  the  obturator  nerve  give  off 
branches  to  the  femoral  artery;  these-  branches  are  also  examples  of  gray  rami. 
The  nerve-  to  the  popliteus  muscle-  sends  a  branch  with  an  artery  into  the  tibia. 
This  is  another  example  of  gray  rami.  The-  parietal  layer  of  the  peritom  inn 
gets  its  nerv<  supply  from  the- gray  rami.  Here  we  apply  Hilton's  law — the 
nerv<  which  supplies  th<  integumenl  supplies  the  muscle-  beneath  the  integu- 
nient  and  the  Lining  beneath  the  muscle,  and  this  nerve-  that  supplies  the  lining 
does  it  through  th<  branch's  called  gray  rami.  The  sympathetic  nerve  is 
developed  from  the  ganglia  upon  tin  posterior  nerve  root  of  the  spina!  cord. 
0n<  -i  t  of  physiologists  say  ii  is  d<  veloped  from  the  suprarenal  capsule-.  The 
sympathetic  nerve  gets  to  its  destination  by  following  the-  somatic  nerves  or 
blood  v<  ssels.  The  sympathetic  nervous  system,  like  the  central  system,  con- 
sists of  nerve  <■<  lis  and  nerve  fibres  which  are-  either  motor,  senseuy  or  com- 
pound. Tin-  trophic  cells  are-  in  the  veite-bral  ganglion  of  the-  sympathetic 
nerve.  The  motor  cells  of  the  sympathetic  originate  in  the'  ganglion  of  the 
sympathetic  and  some  observers  say  thai  the  sensory  fibres  of  the-  sympathetic 
originate  here  also,  but  others  say  tin  sensory  are-  in  the-  cells  of  the-  spinal 
ganglia.  In  tlii>  Latt<  r  case  (which  is  probably  true-)  reflex  action  can  not  take 
place  within  the-  sympathetic  without  involving  the  spinal  nerves.     The-  super- 


ANATOMY    IN    A    NUTSHELL. 


421 


ior  cervical  ganglion  is  reddish-gray  in  color,  about  an  inch  and  a  half  Long, 
situated  behind  the  internal  jugular  vein  and  the  carotid  artery  and  in  front  of 
the  Rectus  capitis  amicus  major  muscle.  It  is  in  front  of  the  transverse  pre- 
ss :  the  second  and  third  cervical  vertebra-,  sometimes  a  little  higher  and 
sometimes  a  little  lower,  and  the  branches  given  off  from  this  superior  cervical 
ganglion  are  rami  efferent*  s. 


LESSON  CXX. 

1.  Four  gray  rami  to  the  first  four  spinal  nerves. 

2.  Branches  to  the  twelfth  cranial  nerve  and  branch  to  the  trunk  of  the 
pneumogastric  and  nervus  jugulaiis  which  divides,  sending  one  branch  to  the 
root  of  the  pneumogastric  and  another  to  the  petrosal  ganglion  of  the  ninth. 

PLATE  CCXXVI. 


BICUSPIDS 


MOLARS 


The  Permanent  Teeth. 

3.  Four  or  five  pharyngeal  branches  which  unite  with  the  ninth  and 
tenth  cranial  nerves  making  the  pharyngeal  plexus,  and  other  branches  to  the 
superior  and  external  laryngeal  nerves. 

4.  Superior  cervical  cardiac  nerve  which  is  behind  the  carotid  sheath, 
behind  or  in  front  of  the  inferior  thyroid  artery,  in  front  of  the  Longus  colli 
where  it  joins  the  cardiac  branches  of  the  tenth  and  middle  cervical  cardiac 
branches  of  the  sympathetic  and  recurrent  and  external  laryngeal  nerves.  It 
descends  behind  or  in  front  of  the  right  subclavian  artery,  along  the  innomi- 
nate artery  to  the  division  of  the  trachea  to  enter  the  deep  cardiac  plexus.  The 
left  one  is  in  front  of  the  left  commoD  carotid  and  the  arch  of  the  aorta,  joining 
the  superficial  cardiac  plexus. 

5.  The  nervi  molles  are  branches  to  the  external  carotid  artery  and  its 
subdivisions.      They  rive  off  subdivisions  (a)  to  the  internal-carotid    artery. 


422  ANATOMY    IN   A    NUTSHELL. 

(b)  tn  the  thyroid  gland,  (c)  to  the  submaxillary  ganglion  which  comes  from 
the  sympathetic  around  the  facial  artery,  (d)  to  the  geniculate  ganglion  of  the 
seventh  and  the  otic  ganglion  of  the  fifth. 

(i.  Sends  branches  to  ligaments  and  bonis. 

7.  Sends  branches  to  the  internal  carotid  artery  which  divides  into  two 
-i  ts,  those  on  its  inner  side  are  called  cavernous  plexus,  those  on  the  other 
side  carotid  plexus.  The  cavernous  plexus  sends  off  (a)  branches  to  the 
pituitary  body,  (l>)  to  the  dura  mater  on  the  sphenoid  bone,  (c)  to  the  mucous 
membrane  of  the  sphenoidal  sinus,  (d)  to  the  third  nerve,  and  the  fourth  nerve, 
and  the  ophthalmic  nerve,  (e)  to  the  carotid  artery,  (f)  to  the  ciliary  ganglion. 

The  carotid  plexus  gives  off  (a)  small  deep  petrosal  to  tympanic  plexus. 
(h)  greal  deep  petrosal  to  Vidian  nerve,  (c)  to  the  Gasserian  ganglion  of  the 
tilth  nerve  and  (e)  to  the  sixth  n#rve. 


LESSON  CXXI. 

The  middle  cervical  ganglion  is  often  absent.  It  is  triangular  in  shape  and 
is  made  by  the  coalescence  of  two  ganglia  and  it  sends  (a)  two  gray  rami  com- 
municantes  to  the  fifth  and  sixth  spinal  nerves,  (b)  branches  to  the  thyroid 
gland  along  the  inferior  thyroid  artery,  (c)  middle  cardiac  nerve  which  is  be- 
hind or  in  front  of  the  first  part  of  the  subclavian  artery,  joins  the  upper 
cardiac  nerve,  recurrent  laryngeal  nerve  and  ends  in  the  dee})  cardiac  plexus. 

On  the  left  side  this  nerve  enters  the  thorax  between  the  left  com- 
mon carotid  and  the  left  subclavian  artery.  It  sends  an  ascending  branch  to 
join  the  superior  cervical  ganglion  and  one  inferior  to  join  the  inferior  cervical 
ganglion.  It  also  sends  a  branch  in  front  of  the  subclavian  artery  to  join  this 
ganglion   called  ansa  Yieussens. 

The  inferior  cervical  ganglion  is  irregular.  In  front  is  the  vertebral  artery, 
behind  a  space  between  the  transverse  process  of  the  last  cervical  and  the  first 
i  lorsal.  It  is  very  close  to  the  first  dorsal  ganglia  with  which  it  sometimes  unites. 
Its  branches  are; 

(a)  Two  gray  rami  to  the  seventh  and  eighth  cervical  ganglia. 

(b)  Branches  to  the  vertebral  artery  which  join  a  branch  from  the  first 
dorsal  to  make  the  vertebral  plexus  which  surrounds  the  vertebral  artery  and 
going  about  it  into  the  circle  of  Willis.  This  plexus  joins  the  roots  of  the  spinal 
nerves   in    the   neck. 

;)  To  the  inferior  cervical  cardiac  which  sometimes  comes  from  the  first 
dorsal;  it  joins  the  middle  cardiac  nerve  and  recurrent  laryngeal  nerve  and 
descends  on  the  trachea  to  the  d<  ep  cardiac  plexus.  On  the  left  side  this  nerve 
is  occasionally  joined  to  the  middle  cervical  to  form  a  common  trunk. 


LESSON  CXX  II. 

The  thoracic  ganglia  are  eleven  in  number;  the  first  one  is  called  stellatum. 
[1  i-  situated  on  the  neck  of  the  first  rib.     The  second  to  the  ninth  are  situated 

on  the  heads  of  the  ribs.  The  tenth  and  eleventh  are  on  the  vertebras.  They 
receive  white  rami  communicantes  from  the  spinal  nerves  and  give  off  gray  rami. 
Each  of  these  ganglia  give  off  rami  efferentes  which  divide  into  external  and 


ANATOMY    IN    A    NUTSHELL.  123 

internal  branches.  The  external  branches  stud  (1)  branches  to  the  meninges 
of  the  cord  (2)  to  the  posterior  division  of  the  spinal  nerves.  (3)  to  the  anterior 
divisions  of  the  spinal  nerves.  These  last  two  pass  to  the  vessels  of  the  skin. 
glands  of  the  skin,  and  the  muscles  of  the  hair.  The  internal  branches  divide 
into  an  upper  set  and  a  lower  set.  The  uppeb  set,  four  or  five,  send  branches 
to  the  vertebrae  and  to  ligaments  and  thoracic  aorta  and  to  the  lungs.  The 
lower  set  give  off  the  great  splanchnic  nerves.  The  great  splanchnic 
nerves  come  from  the  fifth  to  tenth  and  end  in  the  semilunar  ganglion.  The 
LESSER  SPLANCHNIC  nerve  passes  from  the  ninth  and  tenth  and  ends  in  the  renal 
or  solar  plexus.  The  least  splanchnic  comes  from  the  last  dorsal  ganglion 
to  end  in  the  renal  plexus.  The  secretory  fibers  to  the  lower  limbs,  \  A.SO- 
constrictor  to  vessels  of  the  abdomen,  pilo-motor  to  the  circular  fibers  of  the 
rectum,  and  inhibitory  fibers  to  the  longitudinal  muscles  of  the  rectum  de- 
scend from  the  thoracic  tothe  lumbar  region.  Besides  these  there  are  afferenl 
fibers  (splanchnic  sensory)  which  pass  towards  the  posterior  roots  of  the  dor- 
sal nerve.  The  lumbar  ganglia  are  four,  being  set  in  front  of  the  vertebrae.  The 
right  cord  of  the  sympathetic  is  behind  the  inferior  v<  na  cava,  the  left  behind 
the  peritoneum.  White  rami  pass  to  these  ganglia  and  gray  rami  pass  from 
them.  The  rami  efferentes  are  first,  external  divisions  and  second,  internal 
divisions.  The  external  divisions  send  gray  rami  to  the  lumbar  nerves.  The 
internal  divisions  send  (1)  branches  to  the  aorta.  (2)  hypogastric  plexus 
to  the  vertebra?  and  ligaments,  and  additional  vaso  constrictor  fibers  to  the 
renal  vessels  anel  secretory  fibers  to  the  ve  ssels  of  the  lower  limbs  and  i  on- 
BTRICTOR  fibers  to  the  vessels  of  the-  lower  limbs,  pilo-motor  and  motor  fibers 
for  the  circular  and  ixhibitory  fibers  for  the  longitudinal  muscles  of  the'  rectum, 
and  motor  fibers  to  the  uterus  and  vas  deferens  and  round  ligament,  and 
VASO-MOTOR  to  the  penis  anel  motor  fibers  to  the  circular  and  INHIBITORY 
fibers  for  the  longitudinal  muscles  of  the  bladd<  r. 


LESSON  ('Will. 

The  sacral  portion  of  the  sympathetic  ends  in  the  ganglion  of  [mpar.  It 
has  five  ganglia  which  give  off  rami  efft  re  nte  s,  (1)  gray  rami  to  the  sacral  nerves, 
(2)  branches  to  anastomose  with  the  branch*  s  of  the  opposite  side.  <:!)  branches 
to  plexuses  on  the  middle  sacral  artery,  (4)  branches  to  plevic  plexuses 
branches  from  impar  to  tin  coccyx  and  its  ligament  to  the  coccygeal  gland. 
There  are  no  white  rami  in  this  portion  of  the  sympathetic.  They  descend  from 
the  dorsal  region.  Vaso-constrictor  and  secretory  for  the  lower  limbs,  pilo- 
motor for  posterior  part  of  the  body  com<    from  this  region.     "White'  rami  of 

sacral  region"  are'  represented  by  their  viscera]  branches  and  ar<    called 
pe  Ivic  splanchnics.     They  contain  motor  fibers  to  the  longitudinal  muse 
the  bladder  and  for  the  longitudinal  and  inhibitory  of  the  rectum  ami  to  the 
uterus  and  secretory  to  the'  prostate  gland  and  vaso-dilator  to  the  penis. 

White'  rami  enter  tin  c<  rvical  sympathi  tic  from  tin  dorsal ;  some  term  in. mi.' 
in  the  superior  ganglion,  some  in  the  middle  ganglion,  ami  some  in  the  lower 
ganglion.     The  distribution  of  many  an    unknown. 

The  sympathetic  has  three  great  prevertebral  plexuses.     First,  the  cardiac, 


424 


ANATOMY    IX    A    NUTSHELL. 


which  is  situated  below  and  behind  the  arch  of  the  aorta.  For  convenience  it  is 
■divided  into  two  parts,  the  superficial  and  d<  ep.  It  is  formed  by  all  the  cardiac 
branches  and  the  cardiac  branches  of  the  pneumogastric  nerve.  The  three 
cardiac  branches  conic  from  the  three  cervical  ganglia,  the  superior  from  the 
superior  one.  and  the  middle  from  the  middle  one.  and  the  inferior  one  from  the 
inferior  cervical  ganglion.  These  unite  with  the  pneumogastric  nerve  and  form 
the  cardiac  plexuses.  The  superficial  cardiac  plexus  is  made  by  the  left 
superior  cervical  cardiac  and  the  left  inferior  cervical  cardiac  from  the  pneu- 
mogastric, plus  fibers  from  the  deep  plexus.  The  superficial  cardiac  plexus  gives 
off  brandies  to  the  right  coronary  plexus  and  the  left  pulmonary  plexus.  The 
deep  cardiac  plexus  consists  of  left  portion  and  right  portion.     The  left  por- 

PLATE  CCXXVII. 


DENTINF 


PULP 
CAVITY 


m  m 

X  I       *  J  ■  ■    y  r  ■  \  i 


A  Verticle  Section  of  a  Canine  Tooth. 

tion  gives  off  branches  to  the  left  coronary  plexus  and  the  left  auricle.  The 
right  part  gives  off  branches  both  to  the  right  and  left  pulmonary  plexuses 
and  tlir  righl  auricle. 

Thus  we  see  that  the  cardiac  plexus  is  made  by  sympathetic  nerves  plus 
somatic  uerve,  and  the  somatic  nerve  is  the  tenth. 


LESSON  (XXIV. 

Tin     ><>lar  plexus   has   three   uames,    SOLAR,    EPIGASTRIC,   ABDOMINAL  BRAIN. 

It  i<  situated  around  the  coeliac  axis.  It  is  formed  by  the  three  splanchnic 
nerves  from  each  side  and  the  semilunar  ganglia  and  the  right  pneumogastric 
uerve,  and  occasionally  the  left.  It  gives  off  branches  to  the  following  arteries 
ami  these  subdivisions  take  the  nami  s  of  the  arteries  which  they  surround. 


ANATOMY    IX    A    NUTSHELL.  1 2 5 

This  plexus,  like  the  cardiac  plexus,  is  made  up  of  sympathetic  nerves  plus 
somatic  nerve,  which  is  the  tenth  cranial. 

Phrenic  ob  Diaphragmatic  Plexus. 

This  plexus  accompanies  the  phrenic  artery  and  is  larger  on  the  right  than 
on  the  left  side.  At  its  point  of  junction  with  the  phrenic  nerve  is  the  Ganglion 
diaphragmaticum.  This  plexus  is  situated  on  the  under  surface  of  the  Dia- 
phragm near  the  supra  renal  capsule.  Its  branches  are  distributed  to  (1)  In- 
ferior vena  cava.  (2)  supra  renal  capsule,  and  (3)  hepatic  plexus.  There  is  no 
ganglion  on  the  left  side.  It  receives  branches  from  the  semilunar  ganglia  and 
solar  plexus,  also  from  the  phrenic  nerve.  This  plexus  gives  off  branches  to  the 
Diaphragm  and  the  supra  renal  capsules. 

Supra  Renal  Plexi  s. 

This  plexus  surrounds  the  supra  renal  artery  and  its  branches  are  of  large 
size.  At  its  junction  with  the  great  splanchnic  nerve  is  found  a  ganglion.  It 
receives  branches  from  the  solar  plexus  and  semilunar  ganglia,  also  from  the 
phrenic  nerve  and  the  diaphragmatic  plexus.  It  distributes  branches  to  the 
medullary  portion  of  the  suprarenal  capsules. 

Renal  Plexus. 

This  plexus  surrounds  the  renal  artery  and  contains  groups  of  ganglion 
cells.  Its  brandies  of  distribution  enter  the  hilum  of  the  kidney.  This  plexus 
receives  branches  from  the  solar  plexus  ami  semilunar  ganglia,  also  from  the 
aortic  plexus  and  smallest  splanchnic  nerves.  It  sends  branches  of  distribu- 
tion to  the  substance-  of  the  kidn<  y,  the  sp<  rmatic  plexus  anel  the  inferior  vena 
cava. 

Spermatic  Plexus. 

This  plexus  accompanies  the  spermatic  vessels  to  the  testes.  It  rec<  ives 
branches  from  the  renal,  aeirtic,  anel  pelvic  plexus.  It  elistributes  branches  to 
the  spermatic  vessels,  vas  deferens,  and  the  testes. 

In  the  female  this  plexus  follows  the  course  of  the  round  ligament  to  the 
ovarian  plexus  and  i>  distributed  to  the  ovaries  and  fundus  of  the  uterus. 

Cosliac  Plexus. 

This  plexus  is  a  direct  continuation  of  the  solar  plexus  and  surrounds  the 
coeliac  axis.  It  receives  branches  from  the  solar  plexus,  the  lesser  splanchnic 
nerves,  and  the  right  vagus.  It  sub-divides  into  the  (1)  gastric  plexus,  (2) 
hepatic  plexus.  (3)  splenic  plexus. 

The  gastric  plexus  accompanies  the  gastric  artery  along  the  lesser  curva- 
ture of  the  stomach.  It  receives  branches  from  the  coeliac  plexus  and  from  the 
left  vagus  nerve.  It  sends  branches  of  distribution  to  the  stomach  and  to  the 
pyloric    plexus. 

The  hepatic  plexus  is  the  largesl  offset  from  the  coeliac  plexus.  It  receives 
branches  from  the  coeliac  plexus,  the  left  vagus  nerve  and  the  righl  phrenic 
nerve.  It  distributes  branch  s  to  the  pyloric  plexus,  and  branches  to  the  gastro- 
duodenal  plexus,  which  plexus  divides  into  the  righl  gastro-epiploic  plexus  and 
the  pancreatico-duodenal  plexus.     It  also  sends  branches  to  the  cystic  plexus. 

the  right  hepatic  and  the  left  hepal  LC  plexus. 

The  splenic  plexus  accompanies  the  splenic  artery,  and  receives  branches 


421) 


ANATOMY    IN    A    NUTSHELL. 


from  the  cceliac  plexus,  the  right  vagus  nerve,  and  the  left  semilunar  ganglion. 
It  distributes  branches  to  the  pancreatic  and  left  gastro-epiploic  plexus, also  to 
the  substance  of  the  spl<  i  n. 

Superior  Mesenteric  Plexus. 
This  plexus  emerges  from  under  cover  of  the  pancreas  and  surrounds  the 
trunk  of  the  superior  ni<  seiiti  ric  artery.  A  few  ganglia  which  are  found  around 
this  artery  are  called  ganglia  mesenterica.  The  branches  of  this  plexus  are  of 
a  large  size  and  are  white  and  firm.  It  rec<  ives  branches  from  the  solar  plexus. 
the  cceliac  plexus,  and  the  right  vagus  nerve.  It  gives  off  branches  to  the 
pancreas,  all  the  small  intestines,  to  the  ascending  and  half  of  the  transverse 
colon,  and  to  the  pancreatico-duodenal  plexus. 

PLATE  CCXXVIII. 


ANTERIOR  PALATINE   FORAMEN 


ACCESSORY  PALATINE  FORAMINA 


Tin:  Hard  Palate. 


Branches  from  this  plexus  form  .a  secondary  plexus  corresponding  to  the 
primary  and  secondary  loops  of  'he  artery  and  reach  the  small  intestines  by 
spreading  ou1  in  the  m<  s<  ritery. 

\< 'Kin-  Plexus. 

This  plexus  is  situated  on  the  sid(  s  and  in  fronl  of  the  aorta,  between  the 
origins  of  the  superior  and  inferior  mesenteric  arteries. 

It  receives  branches  from  th<  solar  pit  xus  and  semilunar  ganglia,  also  from 
the  lumbar  ganglia.  It  gives  off  branches  of  distribution  to  the  spermatic 
plexus,  the  inferior  mesenteric  plexus,  tin-  hypogastric  plexus,  and  the  inferior 
vena   cava. 

Inferior  Mesenteric  Plexus. 

The  inferior  Mesenteric  plexus  surrounds  the  inferior  mesenteric  artery 
and  divides  into  a  number  of  secondary  plexuses.  Upon  this  artery  is  a  gang- 
lion  called   the  inferior  mesenteric  ganglion.     This  plexus   receives  branches 


ANATOMY    IN    A    NUTSHELL.  427 

from  the  aortic  plexus.     It  distributes  branches  to  half  of  the  transverse  colon 
and  the  descending  colon,  to  the  sigmoid  plexus,  to  the  superior  hemorrhoidal 

plexus,  and  to  the  pelvic  plexus. 


LESSON  CX XV. 
Hypogastric  Plexus. 

This  plexus  is  situated  in  front  of  the  promontory  of  the  sacrum  between 
the  common  iliac  arteries.  It  contains  no  ganglia.  It  receives  branches  from 
the  aortic  plexus,  the  lumbar  ganglia.  It  bifurcates  below  into  two  lateral 
halves  which  form  the  pelvic  plexuses.  This  plexus  is  made  up  exclusively  of 
sympathetic  nerves. 

Pelvic  Plexus. 

This  is  situated  at  the  side  of  the  rectum  and  bladder  in  the  male,  and  in 
the  female  it  is  at  the  side  of  the  rectum,  bladder  and  vagina.  It  accompanies 
the  branches  of  the  internal  iliac  artery  and  supplies  the  pelvic  viscera.  This 
plexus  contains  small  ganglia.  It  is  formed  by  the  two  lateral  continuations  of 
hypogastric  plexus,  branches  of  the  sacral  part  of  the  gangliated  cord,  branches 
of  the  second,  third  and  fourth  sacral  nerves.  It  sends  branches  of  distribution 
to  the  middle  hsemorrhoidal  plexus,  the  inferior  hemorrhoidal  plexus,  the  vesical 
plexus,  the  prostatic  plexus,  the  vaginal  plexus,  and  the  uterine  plexus. 

The  middle  hsemorrhoidal  plexus  is  situated  on  the  sides  of  the  rectum,  and 
is  formed  by  branches  from  the  pelvic  plexus.  It  communicantes  above  with 
the  superior  hsemorrhoidal  plexus  and  below  with  the  inferior  hsemorrhoidal 
plexus.     It  is  distributed  to  the  rectum. 

The  inferior  hsemorrhoidal  plexus  arises  from  the  back  part  of  the  pelvic 
plexus  and  joins  with  branches  from  the  superior  and  middle  hsemorrhoidal 
plexuses.     It  is  distributed  to  the  rectum. 

The  vesical  plexus  arises  from  the  fore  part  of  the  pelvic  plexus,  and  is 
formed  chiefly  by  fibers  from  the  third  and  fourth  sacral  nerves.  Tin  nerves 
sent  off  pass  on  each  side  of  the  bladder.  This  plexus  is  divided  into  two 
groups,  (1)  superior  group,  (2)  inferior  group.  It  distributes  branches  to  the 
bladder,  the  vesiculse  seminales,  the  vas  deferens,  the  spermatic  plexus. 

The  prostatic  plexus  is  a  continuation  downward  of  the  pelvic  plexus  and 
is  situated  around  the  prostate  gland.  Its  nerves  are  of  large  size.  On  the 
sides  of  the  gland  are  several  ganglionic  masses  from  one-fourth  to  one-half  an 
inch  in  length  (ganglia  prostatica  of  Muller).  It  is  joined  by  branches  of  the 
internal  pudic  nerve.  It  distributes  branches  to  the  prostate  gland,  the  ves- 
iculse seminales,  small  cavernous  nerves  to  the  erectile  structure  of  the  penis, 
corpora  caveronsa  and  corpus  spongiosum,  barge  cavernous  nerve  joins  the 
dorsal  branch  of  the  pudic  nerve  and  supplies  the  corpora  cavernosa  and  corpus 
spongiosum. 

The  vaginal  plexus  arises  from  the  lower  part  of  the  pelvic  plexus  and  is 
composed  hugely  of  sacral  nerves.  It  is  situated  on  the  sides  of  the  vagina. 
It  gives  off  branches  to  the  erectile  tissue  of  the  vagina,  the  mucous  membrane 
of  the  vagina,  and  a  few  twigs  to  the  clitoris. 

The  uterine  plexus  arises  from  the  upper  pari  of  the  pelvic  plexus  and  ac- 


428 


ANATOMY    IN   A    NUTSHELL. 


companies  the  uterine  artery  between  the  layers  of  the  broad  ligament  It 
receives  a  few  twigs  from  the  ovarian  plexus.  It  distributes  branches  to  the 
cervix  and  body  of  the  uterus.     Other  filaments  pass  separately  into  the  body 

oJ  the  Qterus  and  fche  Fallopian  tubes.  There  are  ganglionic  enlargements 
found  mi  these  filaments. 

PLATE  CCXXIX. 


C'JRRUGATOR     SUPERCILII 


ORBICULARIS 
PALPEBRARUM 


TENDO  OCULI 

LEVATOR   ALBII     SUPERIORIS 

LEVATOR    LABII  SUPERIORIS 


ANTERIOR    NASAL    SPINE 

LEVATOR  ANGULI     ORIS 

INCISIVE    FOSSA 
COMPRESSOR     NARIS 

OEPRFSSOR       ALAE    NASI 


LEVATOR       MENTI 


OEPRESSOR  LABII    INFERIORS  £ 
DEPRESSOR    ANGULI    ORIS 


GROOVE    FOR    FACIAL    ARTERY 


Tin:  Bones  of  the  Orbit. 


LESSON  CX  XVI. 

The  gray  rami  coimn  unit-antes  originate  in  cells  of  the  vertebral  ganglion, 

^d  in,,,,  here  pass  to  their  destination  byway  of  the  spinal  nerves,  (1)  to  ad- 

J;,""!/  y:"';f  •'•  '"'  "'  the  Prevertebral  plexus,  (3)  directly  to  the  viscera  and 

vessels.      Ihe.r  trophic  cells  are  in  these  ganglia  where  they  originate.     These 


ANATOMY    IN    A    NUTSHELL.  429 

nerves  are  indigenous  in  every  part  of  the  spinal  cord.  The  branches  that  pass 
to  the  femoral  artery  from  the  Anterior  Crural  and  Obturator  are  gray  rami 
communicantes,  and  through  these  branches  the  non-medullated  axis-cylinder 
processes  of  the  sympathetic  ganglion  cells  reach  the  vessels,  fascia',  bones, 
cartilages,  and  periosteum  of  the  lower  extremity. 

A  gray  ramus  communicans  passes  to  the  tibia  from  the  branch  of  the  in- 
ternal popliteal  nerve  which  passes  to  the  Popliteus  muscle.  Each  spinal  nerve 
is  joined  near  its  origin  by  a  gray  ramus  communicans  from  the  sympathetic 
gangliated  cord.  The  superior  cervical  ganglion  gives  off  four  gray  rami  com- 
municantes to  the  first  four  cervical  nerves.  These  rami  may  come  from  the 
sympathetic  nerve  below  the  ganglion.  The  middle  cervical  ganglion  s<  ntds  two 
gray  rami  to  the  fifth  and  sixth  cervical  nerves.  The  inferior  cervical  ganglion 
sends  two  gray  rami  to  the  seventh  and  eighth  nerves.  The  first  dorsal  ganglion 
(stellatum)  of  the  sympathetic  or  the  last  cervical  sends  a  gray  ramus  to  the  first 
dorsal  nerve.  One  ganglion  may  send  gray  rami  to  two  nerves,  or  two  gray 
rami  to  one  nerve.  In  the  lumbar  and  sacral  regions  the  gray  rami  are  long  and 
pass  downward  and  outwards  over  the  bodies  of  the  vertebrae  to  reach  the  an- 
terior division  of  the  nerve.  In  the  lumbar  region  they  pass  under  the  Psoas 
magnus  muscle. 

The  white  rami  communicantes  originate  in  the  motor  roots  of  the  cranial 
and  spinal  nerves.  Some  of  these  white  rami  pass  through  the  vertebral  gang- 
lia without  interruption,  while  others  arborize  with  cells  in  the  vertebral  gang- 
lia. The  white  rami  communicantes  are  indigenous  in  the  thoracic  and  upper 
lumbar  regions  only,  while  the  gray  rami  are  indigenous  in  all  parts  of  the  cord. 
The  white  rami  may  be  called  the  visceral  divisions  of  the  spinal  nerves.  Al- 
though the  white  rami  are  for  the  most  part  derived  from  the  ventral  or  an- 
terior roots,  yet  some  of  them  come  from  the  dorsal  or  posterior  roots.  The 
white  rami  from  the  hist  two  lumbar,  and  peihaps  also  from  the  third  and  fourth 
lumbar  nerves,  pass  forward  by  themselves  or  in  company  with  the  gray  rami 
to  join  the  upper  pait  of  the  lumbar  gangliated  cord.  The  fifth  lumbar  and  in  si 
sacral  do  not  have  white  rami  while  the  third  sacral  and  possibly  tin  s(  cond  and 
fourth  have  both  white  and  gray  rami.  The  fifth  sacral  and  coccygeal  nerves 
hav<     no    white   rami. 

In  Plate  CXCVI1 1  we  s<  e  the  gray  and  white  rami  communicantes.  A,  B,  ( '. 
and  D  represent  white  or  n  <  dullat<  d  rami,  while  E,  F,  G,  H,  L,  M,  N,  r<  pres<  nt 
tlu  gray  or  non-medullated  ran  i.  A  passes  from  the  anterior  or  ventral  root 
to  the  sympathetic  ganglion  of  its  own  segmenl  through  which  it  passes  to  the 
ganglion  below.  B  has  a  similar  origin  but  ends  in  the  ganglion  of  its  own 
segment.  Chas  a  similar  origin  and  passes  through  the  sympathetic  ganglion 
of  its  own  segment  to  a  prev<  rtebral  plexus  or  directly  to  visc<  ra.  1 )  has  a  sim- 
ilar origin  and  passes  through  the  sympathetic  ganglion  of  its  own  stum,  nt  to 
end  in  a  higher  ganglion.  F  originates  in  the  sympathetic  ganglion  and  passes 
along  the  posterior  nerve  rod  to  the  dura  mater  of  thi  mn\.  G  originates  in 
the  sympathetic  ganglion  and  passes  along  the  posterior  division  of  the  spinal 
nerve  to  its  destination.  II  originates  in  the  sympathetic  ganglion  ami  passes 
along  the  anterior  division  of  the  spinal  nerve  t<>  iis  destination.     It  passes  to 


PLATE  CCXXX. 


CEREBRAL  CORTEX 


OPTIC 


THALAMUS 


CORPORA  QUADRIOEWINA 


CEREBELLAR 
CORTEX 


NUCLEUS 
DENTATUS 


\  prosencephalon 
(  [cerebrum) 


mesencephalon 
(mid  brain) 


NUCLEUS    FASCICULUS    CUNEATUS 
NUCLEUS   FASCICULUS   GRACILLIS 


NUCLEI        I     METENCEPHALON 
PONTIS        /pONSiCEREBELLUM 


ULBAR  V.      MYELENCEPHALON 

NUCLEI  (  MEQULLA  OBLONGATA 


SPINAL  CORD 


Showing  the  Sensory  Pathways  to  the  Brain. 
330 

(Modified  from  Eckley's  Jackson.) 


ANATOMY    IN    A    NUTSHELL.  431 

somatic,  vasomotor,  pilo  motor,  and  secretory.  K  originates  in  the  sympa- 
thetic ganglion  and  passes  along  the  recurrent  branch  to  the  vertebrae,  ligaments, 
spinal  vessels,  and  dura  mater  of  the  cord.  L  originates  in  the  sympathetic 
ganglion  and  passes  along  the  gray  rami  for  a  short  distance  then  it  leaves  it  to 
pass  to  the  vertebra?,  intercostal  and  lumbar  vessels.  M  originates  in  the  sym- 
pathetic ganglion  and  like  all  others  that  originate  in  this  ganglion  are  called 
rami  efferentes.  X  originates  in  the  sympathetic  ganglion  and  pass  to  the  gang- 
lion above  it  or  the  ganglion  below  it. 


LESSON  ( XXV II. 

"The  gross  anatomy  of  the  cervical  sympathetic  gives  no  idea  of  its  true 
anatomical  relations  as  revealed  by  physiological  experiments  and  pathological 
phenomena.  The  physiological  connections  as  at  present  understood  mar  be 
summed  up  as  follows: 

1.  Pupillo-dilator  fibers  pass  by  white  rami  communicantes  from  the 
first,  second  and  third  thoracic  nerves  and  ascend  in  the  sympathetic  cord  to 
the  superior  cervical  ganglion  to  form  arborizations  round  its  cells.  Thence 
gray  fibers  pass  to  the  Gasserian  ganglion  and  reach  the  eye-ball  by  the  ophthal- 
mic division  of  the  fifth  and  long  ciliary  nerves. 

2.  Motor  fibers  to  the  involuntary  muscles  of  the  orbit  and  eyelids  from 
the  fourth  and  fifth  thoracic  nerves  follow  a  similar  course. 

3.  Yaso-motor-fibers  to  the  head,  secretory  fibers  to  the  submaxillary 
gland,  pilomotor  fibres  to  the  head  and  neck  are  derived  from  the  upper  thor- 
acic nerves  and  reach  their  areas  of  distribution  after  a  similar  interruption  in 
the  superior  cervical  ganglion. 

4.  The  accelerator  fibers  of  the  heart  are  derived  from  the  upper  tho- 
racic spinal  nerves,  and  end  similarly  in  the  middle  and  lower  cervical  ganglion 
gray  fibers  in  the  cervical  cardiac  nerv<  s  completing  the  connection." — (Gerrish). 

"  A  patient  with  laceration  of  the  cervix  goes  through  five  stages:  (1)  irri- 
tation;  (2)   INDKiESTION;  (3)   .MALNUTRITION!  (4)    ANEMIA;   (5)    NEUROSIS. 

These  stages  will  appear  if  the  patient  has  a  neuropathic  constitution  or 
diathesis. 

"A  general  summary  of  the  abdominal  brain  is:  that  (a)  it  presides  over 
nutrition;  (b)  it  controls  circulation:  (c)  i1  controls  gland  secretion;  (d)  it  pre- 
sides over  the  organs  of  g<  n<  ration;  (e)  it  influences  in  a  dominant,  though  not 
an  absolute  control  its  peripheral  visceral  automatic  ganglia." — (Byron  Rob- 
inson). 

LESSON  CXXVIII. 

(  nvi.ii  Tim  ,  Paths.  (Pint,  s  CCX  X  \-( '( 'X  X  X  I-( '(  XXXIII). 
The  cortex  of  each  hemisphere  of  tin  brain  is  in  communication  with  the 
opposite  half  of  the  body  by  means  of  fibers  conducting  impulses  to  and  from 
it.  These  fibers  maybe  divided  into  two  sets,  according  to  the  dir<  ction  of  con- 
duction :  centrifugal,  or  motor,  which  conduct  <  xcitations  from  the  cortex  to  the 
various  muscles  of  the  body:  and  centripetal,  or  sensory,  which  convey  excita- 


PLATE  ('(  XXXI. 


CEREBRAL  CORTEX 


prosencephalon 
(cerebrum) 


mesencephalon 
(mid  brain) 


NUCLEUS   FASCICU 
NUCLEUS  FASCICU 


NUCLEI         I    MESENCEPHALON 
PONTIS         ((PONS  «  CEREBELLUM^ 


MYELENCEPHALON 
MEDULLA  OBLONGATA) 


>    SPINAL 


Showing  the  Motor  Pathways  From  the  Biiain. 
432 

(Modified  from  Eckley'a  Jackson.) 


ANATOMY  IN  A  NUTSHELL.  433 

tions  from  the  skin,  mucous  membranes,  bones,  special  sense  organs,  to  the 
cortex,  where  are  produced  in  an  unknown  way  what  we  call  sensation.  Each 
half  of  the  body  is  thus  represented  in  or  projected  upon  the  cortex  of  the  opposite 
hemisphere;  hence  the  name  of  projection  fibers  given  to  those  fibers  of  the 
brain  through  which  communication  is  maintained.  (Plate  CLXXXI).  Thev 
are  in  many  instances  collected  into  distinct  bundles;  so  that  we  may  speak  of 
motor  and  sensory  tracts  or  paths,  meaning  thereby  definite  groups  of  fibers 
along  which  motor  or  sensory  impulses,  as  the  case  may  be,  travel.  Moreover 
these  groups  of  fibers  often  arise  from  or  terminate  hi  fairly  definite  areas  of  the 
cortex,  which  areas  are  usually  called  centers.  (Plate  CLXXXI  1 1).  Thus, 
that  from  which  springs  the  fibers  that  conduct  impulses  to  the  muscles  which 
produce  the  movements  of  the  hand  may  be  called  the  motor  center  of  the  hand; 
that  which  receives  the  fibers  along  which  visual  impressions  travel  is  the 
center  of  sight. 

Of  the  many  ways  in  which  impulses  may  travel  between  the  brain  and  the 
spinal  cord,  the  following  (1),  (2),  (3),  (4),  (5),  (6),  are  the  most  important  that 
have  been  demonstrated.  If  these  impulses  travel  through  the  cerebellum  we 
call  the  way  they  pass  the  indirect  route,  but  if  they  miss  the  cerebellum  we  call 
the  way  they  travel  the  direct  route.  This  applies  to  both  motor  and  sensory 
impulses. 

Sensory  impulses,  which  are  afferent,  (centripetal)  take  the  following  routes: 

(1.)  They  travel  by  the  way  of  the  tracts  of  Goll  and  Burdach 
(fasciculus  gracilis  et  cuteatus)  (Plate  CCXXX)  to  the  nuclei  gracilis  et  cuneatus 
by  means  of  neurones  of  the  first  order.  By  way  of  explanation  we  might  say 
that  a  neurone  system  consists  of  a  group  of  nerve  fibers  and  their  cells  of  origin. 
From  nuclei  gracilis  et  cunetus  the  impulses  travel  by  neurones  of  the  second 
order  through  the  mesial  fillet  to  the  optic  thalamus.  The  mesial  fillet  crosses 
to  the  opposite  side  and  gives  off  collaterals  to  (a)  the  bulbar  nuclei,  (1))  to  the 
mid-brain.  From  the  optic  thalamus  the  impulses  travel  to  the  cerebral  cortex 
by  the  way  of  neurones  of  the  third  order,  however  some  of  those  of  the  second 
order  may  pass  through  the  optic  thalamus  to  the  cerebral  cortex  uninterrupted. 
Thus  we  see  two  neurone  systems  may  carry  the  impulses  to  the  cortex  or  it 
may  take  three.  Muscle  and  joint  sensations  travel  through  these  i  racts.  This 
route  is  direct  because  it  does  not  travel  through  the  cerebellum. 

(2.)  After  passing  through  neurones  of  the  first  order  by  the  way  of  col- 
laterals to  the  gray  matter  of  the  anterior  horn,  the  impulses  travel  through  the 
AlNTERO-lateral-  ground  bundle  (fasciculi  proprii)  by  neurones  oi  the  second 
order  to  the  optic  thalamus.  While  in  the  posterior  longitudinal  bundle  (fas- 
ciculus longitudinalis  medialis)  collaterals  are  given  to  the  bulbar  nuclei  and 
mid-brain.  From  the  optic  thalamus  neurones  of  the  third  order  pass  to  the 
Cortex.      This  route  is  direct  and  conveys  cutaneous  and  painful  sensations. 

(3.)  After  passing  through  neurones  of  the  first  order  by  the  way  of  col- 
laterals to  the  cells  of  gray  matter  of  the  cord,  they  travel  by  the  way  of  the 
tracts  of  Gower's  (antero-lateral  ascending)  by  neurones  of  the  second  order 
through  the  dorsal  region  of  the  pons  and  medulla  to  mid-brain  and  optic  thal- 
amus.     From    the   optic    thalamus   neurones   of   the    third   order   complete   the 


434 


ANATOMY  IN  A  NUTSHELL. 


course  to  the  cortex.     This  route  is  direct  and  conveys  cutaneous  and  painful 
sensations. 


LESSON  (XXIX.  (Plate  CCXXX). 
(4.)  This  route  is  indirect  because  it  passes  through  the  cerebellum.  Neu- 
rones of  the  first  order  carry  impulses  to  nuclei  gracilis  et  cuneatus  by  way  of 
i  i;  vers  ok  Goll  and  Btjrdach  just  as  in  the  direct  route.  From  here  neurones 
of  the  second  order  through  the  restiform  bodies  (inferior  peduncles  of  the  cere- 
bellum) of  the  same  or  opposite  side  to  the  vermis,  giving  off  collaterals  to  the 
nuclei  in  the  cerebellum,  such  as  nucleus  dentatus.     Impulses  now  pass  from 

PLATECCXXX1I. 

OPTIC    NERVE 

INTERNAL    CAROTID    ARTERY  I         OPHTHALMIC    ARTERY 

\  /  ANTERIOR     CLINOIO     PROCESS 

TROCHLEAR    NERVE  \  /     /  rn„r 

\  \  /    /    TROCHLEAR     NERVE. 

DIAPHRAGMA  SELLAE  "^^^^^^T^nA  ^gSS?  ^/W'M/^^M^P^——   LACHRYMAL  BRANCH 

PITUITARY    FOSSA.  -J|f   ^FIW \  ."'     (R^^f^/    ft      -  '  f^T 

■7^Ju\ '" 'f^'fiS. ■":;:•-    A-.^^-^p'   -^>'-^V^^-l0CUL0-M0T0R  NERVE.  -SUP.  DIVISION 

ll^^.X  1    /^^^'\:::^-V5^    ~g^3x//       NASAL  BRANCH  OF  OPHTHALMIC  NERVE 

SPHENOIDAL  SINUS    ^m^^y^My^m^    x- ■" -  ■   "---■^S— ^3^y\^^0CUL0-M0T0R  NERVE  (INF.  DIVISION; 

ADUCENT    NERVE^^^^y^ftQ-X^^^^__  "'   ^  ABDUCENT  NERVE 

SPHENOID  B0NEs£— ^J^^Tp-J^  MAXILLARY  DIVISION  OF  TRIGEMINAL    NERVE 

INTERNAL  CAROTID  ARTERY/   /(^ar  ^y  »f'*pT^/^.N\\^^^H 

CAVERNOUS   SINUS  /  /        /  \   \      \ 

'  /        /  \     \         FORAMEN  OVALE 

OPHTHALMIC    DIVISION  OF    TRIGEMINAL    NERVE        /        /  \       \ 

/  /  \      INFERIOR  MAXILLARY      DIVISION  OF  TRIGEMINAL    NERVE 

SOP.    MAXILLARY  DIVISION  OF  USEMINAL  NERVE — '  /  \ 

INF.  AXILLARY  DIVISION  OF  TRIGEMINAL  NERVE  '  MOTOR  RO 

The  Cavernous  Sinus  (Modified  from  Cunningham.) 

the  vermis  to  the  nucleus  dentatus  by  way  of  neurones  of  the  third  order.  From 
t  he  nucleus  dentatus  impulses  pass  to  the  red  nucleus  of  the  opposite  side  through 
the  superior  peduncles.  This  is  done  by  means  of  neurones  of  the  fourth  order. 
From  the  red  nucleus  neurones  of  the  fifth  order  pass  to  the  optic  thalamus. 
From  the  optic  thalamus  neurones  of  the  sixth  order  pass  to  the  cortex. 

!■">.!  These  Impulses  pass  in  the  direct  cerebellar  tract  (fasciculus 
spino-cerebellaris  dorso-lateralis)  then  through  the  inferior  peduncles  of  the 
cerebellum  to  the  vermis  of  the  same  and  opposite  side  by  means  of  neurones  of 
the  second  order.  Collaterals  are  given  off  to  the  nucleus  dentatus.  From 
the  vermis  neurones  of  the  third  order  pass  to  the  nucleus  dentatus  and  from 
here  by  in  urones  of  the  fourth  order  to  the  red  nucleus.  From  the  red  nucleus 
to  the  optic  i  hah)  inns  by  n<  urones  of  the  fifth  order  and  from  the  optic  thalamus 
to  the  cortex  by  neurones  of  the  sixth  order.  Neurones  of  the  first  order  trans- 
mit impulses  to  cells  in  the  columns  of  Clark  by  the  way  of  collaterals.  This 
route  is  indirect  because  it  passes  through  the  cerebellum. 


AX  ATOMY  IN  A  NUTSHELL.  435 

(6.)  In  this  route  impulses  pass  up  (Power's  tract  (fasciculus  spino- 
cerebellaris  ventro-lateralis)  by  neurones  of  the  second  older  to  the  mid-brain. 
From  here  they  reach  the  superior  worm  by  the  way  of  the  superior  peduncles 
of  the  cerebellum.  The  remainder  of  the  route  is  the  same  as  that  in  route  4 
and  5.  Neurones  of  the  first  order  give  collaterals  to  cells  of  the  gray  matter. 
The  indirect  route  may  take  six  neuroxk  SYSTEMS  to  complete  its  course  while 
the  direct  takes  only  three.  This  route  is  indirect  because  it  passes  through 
the  cerebellum. 


LESSON  CXXX.  (Plate  CCXXXI). 

The  motor  impulses,  which  are  efferent  (centrifugal)  take  the  following 
routes : 

(1.)  By  the  way  of  the  pyramidal  tract  without  passing  through 
the  cerebellum.     This  route  is  direct. 

Impulses  in  this  route  pass  from  the  cortex  through  the  corona  radiata. 
internal  capsule,  and  pyramidal  tracts  to  the  lower  end  of  the  medulla  by  neu- 
rones of  the  first  order.  From  the  lower  end  of  the  medulla  the  fibers  pass  in 
the  following  ways:  (a)  most  of  them  cross  to  the  opposite  side  in  the  decussa- 
tion of  the  pyramid  to  descend  in  the  crossed  pyramidal  tract  (fasciculus  cere- 
bro-spinalis  lateralis)  to  end  in  the  gray  matter  of  the  anterior  horn.  (1>)  some 
of  the  fibers  descend  in  the  direct  pyramidal  tract  (fasciculus  cerebro-spinalis 
ventralis)  to  end  in  the  gray  matte  r  of  the  anterior  horn,  (c)  the  remaining  fibers 
d<  set  rid  in  the  crosst  d  pyramidal  tract  of  the  same  side  to  e  nd  in  the  gray  matter 
of  the  anterior  horn.  From  the  cells  in  the  gray  matter  of  the  anterior  horn  neu- 
rones of  the  second  order  carry  impulses  to  the  muscle.  Thus  we  see  that  two 
neurone  systems  will  carry  a  motor  impulse  from  the  cortex  to  the  muscle1. 

(2.)  By  the  way  of  corpus  striatum  and  mid-brain  without  passing 
THROUGH  THE  CEREBELLUM.     This  route  is  direct. 

These-  impulses  pass  by  neurones  of  the  first  order  to  the-  corpus  striatum. 
Most  of  these'  come  from  the  frontal  region.  They  now  pass  by  neurones  of  the 
se'e-eind  order  to  the'  mid-brain.  From  the'  mid-brain  impulses  pass  by  neurones 
of  the  third  order  by  the'  antero-lateral  de  scending  tract  to  end  in  the'  gray  matter 
of  the' 'anterior  horn.  Neurones  of  the  fourth  order  now  carry  the  impulse'  to 
the  muscles  over  the'  anterior  roots  of  the  spinal  nerves. 

(3.)  By  way  of  the  pyramidal  TRACT,  NUCLEI  PONTIS,  CEREBELLUM,  BUL- 
BAR nuclei.  This  route  passes  through  the  cerebellum  therefore  it  is  an  in- 
direct route.  Impulses  pass  by  the  neurones  of  the  first  order  through  the 
corona  radiata, internal  capsule,  and  pyramidal  tract  to  the  pons.  From  the- 
pontis  nuclei  impulse's  pass  by  the'  middle'  peduncle's  to  the'  cortex  of  the  opposite 

side  of  the-  cerebellum.  From  here  neurones  of  the  third  order  carry  the  im- 
pulses to  the'  dentate'  nucleus.  Neurones  of  the  fourth  order  pass  from  the 
dentate'  nucleus  to  the  bulbar  nuclei.  Neurones  of  the  fifth  order  pass  from 
the  bulbar  nuclei  to  end  in  the  gray  matte  r  of  the  and  rior  horn  and  from  here 

neurones  of  the'  sixth  order  pass  to  the  muscle  s. 


PLATECCXWIII. 


CEREBRAL  CORTEV 


PROSENCEPHALON 
( ERERKUM) 


MESENCEPHALON 


i    METENCEPHALON 
PONTIS  /  /PQNS*CEKEBELLUM| 


myelencephalon 
(medulla  oblongata) 


NUCLEUS  FASCICULUS  CUNEA"r|£     -    - 
NUCLEUS  FASCICULUS   C-RACILLIS 


SPINAL  COHD 


Showing  Both  Sknsoiiy  and  Motor  Pathways. 
Modified  from  Eckley- Jackson.) 


436 


ANATOMY  IN  A  NUTSHELL. 


437 


Every  sensory  point  of  the  body  is  connected  to  every  motor  point  by  a  re- 
flex pathway,  and  all  nerve  impulses  conform  to  the  reflex  type. 

A  reflex  impulse  may  pass  over  many  different  paths  between  any  given 

sensory  point  and  motor  point.  (Plate  CCXXXII)  show-  both  afferent  and 
efferent  pathways. 

The  brain  is  a  collection  of  gray  ganglia  connected  by  white  commissures. 
(Xote).  The  middle  commissure  is  gray,  but  it  is  not  a  commissure  in  the  true 
sense  because  it  has  not  fibers  hi  it. 

When  we  can  name  and  define  the  commissures  of  the  brain  and  give  the 
boundaries  of  all  the  ventricles  and  describe  each  structure  which  helps  to 
make  these  boundaries,  then  we  understand  something  of  the  brain. 


LESSOX  CXXXI. 


The  Transverse  Commisures  are : 

1.  Anterior  commissure.  See  page  347 

2.  Middle  commissure.     See  page  348 

3.  Posterior  commissure.  See  page  348 

4.  Optic  commissure.     See  page  366 

5.  Corpus  callosus.     See  page  350 

6.  Pons  varolii.     See  page  362 

7.  Fornix,  also  longitudinal.  Page  348 

8.  Sup.  or  ant.  medullary  velum 
(valve  of  Yieussens.) 

9.  Inf.  or  post,  medullary  velum 


The  Longitudinal  commissures  are: 

1.  Olfactory  tracts.     See  page  365 

2.  Tsenia  Semicircularis.  See  page  356 

3.  Crura  cerebri.     See  page  363 


4.  Processus-e-cerebello-ad-testes. 
page  354 

5.  Peduncles  of  pineal  glad. 

6.  Fornix.     See  page  348 

7.  Gyrus  Fornieatus. 

8.  Lamina  cmerea.     See  page  345 

9.  Infundibulum. 

10.  Fasciculus  uniformis. 


See 


LESSON  CXXXII. 
Third  Ventricle. 


ROOF. 

1.  Corpus  callosum.     See  page  350 

2.  Fornix.     See  page  348 

3.  Velum  interpositum  (Tela  choroidea 
superior).     See  page  351 

4.  Epithelium. 

floor. 

1.  Tegmental  portion  of  the  diverg- 
ing crura  cerebri.     See  page  363 

2.  Posterior  perforated  spare 

3.  Corpora  albican i in.     See  pa.ue  349 

4.  Tuber  cinereum. 

5.  Infundibulum. 

6.  Lamina  cinerea  (anterior  wall). 


WTKRlnR   BORDER. 

1.  Anterior  commissure.  See  page  347 

2.  Anterior  pillars  of  fornix.    Page  349 

3.  Foramen  of  Monro.      Seepage  ".11 


P<  istkriok  BORDER. 

1.  Posterior  commissure.     Page  348 

2.  Aquedud   of  Sylvius.     Page  341 

3.  Epithelium  from  pineal  body 

to  velum  interpositum  (tela  choroi- 
dea superior). 

BIDES. 

1 .  ( tptic  thalamus.   See  page  :, 


1  >,S  ANATOMY  IX  A   NUTSHELL. 

PLATE  CCXXXIV. 

BREGMA. 


TEMPORAL 
RIDGES. 


3» 

CO 

O 


NION. 


—  BONE  S  — 
l-FRONTAL.  6-MALAR. 


7-LACHRIMAL. 
8-SDR  MAXILLARY. 
9-NASAL. 
KHNF.  MAXILLARY. 


2-PARIETAL. 

3-0CC1P1TAL. 

4-TEMPORAL. 

5-SPHENOID. 

— -SUTURES- 

CORONAL-  FROM  PTERION  TO  PTERION.   BETWEEN  FRONTAL  AND  PARIETALS. 
SAGITTAL-  FROM  BREGMA  TO  LAMBDA  -  BETWEEN  THE  PARIETALS. 
LAMBDOID- FROM  ASTERION  TO  ASTERION    BETWEEN  PARIETAS  AND  OCCIPITAL. 

The  Sutures  of  the  Skull. 

LESSON  CX XX III. 

L  \ti:i;  \i.  Ventricle: 

ROOF-  OUTER  SIDE. 

L.  Corpus  callosum.     See  page  350  1.  Corpus   callosum.     See  page  350 

'''•"nK-  INNKK  SIDE. 

1.  Caudate  nucleus.  1.  Corpus  callosum.     Seepage  :r><> 

2.  Taenia  semicircularis.     See  page  356    2.   Fornix.     See  page  348 

::-  Lamina  cornea.  3.  Septum  lucidum.     See  page  351 

4.  Choroid  plexus. 

").  optic  thalamus.     Sec  page  352 

6.  Fornix.     See  p.-iu<'  '■'<  18 


ANATOMY  IX  A  NUTSHELL.  439 

LESSON  CXXX1Y. 

Fourth  Ventricle. 
The  ruof  or  posterior  boundary  Is  formed  by  the  cerebellum  and  has  the 
following  points  for  consideration: 

1.  Superior  peduncles  of  cerebellum.     See  page  354 

2.  Valve  of  Vieussens,  anterior  or  superior  medullary  velum. 

3.  White  matter  of  vermiform  process  of  cerebellum. 

4.  Inferior  medullary  velum. 

5.  Epithelial  lining  of  choroid  plexus. 

6.  Tela  choroidea  inferior. 

7.  Obex. 

8.  Ligulse. 

The  floor  or  anterior  boundary  is  formed  by  the  pons  and  medulla  and  has 
the  following  points  for  consideration: 

1.  Eminentia  teres. 

2.  Fovea  superior. 

3.  Conductor  sonorus. 

4.  Locus  caeruleus. 

5.  Fovea  inferior. 

6.  Ala  cinerea  (trigonum  vagi.) 

7.  Trigonum  hypoglossi. 

8.  Tuberculum  acusticum. 


LESSON  CXXXV. 
The  first  cranial  nerve  is  called  olfactory.     It  leaves  the  cranium  through 

the  cribriform  plate  of  the  ethmoid.  One  disease  of  this  nerve  is  called  anosmia. 
The  second  cranial  nerve  is  called  optic.  It  leaves  the  cranium  through  the 
optic  foramen.      One  disease  of  this  nerve  is  optic  neuritis. 

The  third  cranial  nerve  is  called  motor  oculi.  It  leaves  the  cranium  through 
the  anterior  lacerated  (sphenoidal)  fissure.  Paralysis  of  this  nerve  will  canst1 
ptosis. 

The  fourth  cranial  nerve  is  called  trochlear.  It  leaves  the  cranium  through 
the  anterior  lacerated  (sphenoidal)  fissure.  Paralysis  of  this  nerve  will  cause 
diplopia. 

The  fifth  cranial  nerve  is  called  trifacial.  The  ophthalmic  division  Leaves 
the  cranium  through  the  sphenoidal  fissure.  This  division  of  the  nerve  is  sub- 
ject to  malarial  and  septic  poisons.  The  superior  maxillary  division  Leaves 
the  cranium  through  the  foramen  rotundum.  The  inferior  maxillary  division 
leaves  the  cranium  through  the  foramen  ovale.  These  last  two  divisions  are 
subject  to  rheumatic  influences.  The  fifth  nerve  is  involved  in  tic-douloureux, 
neuralgia,   and   toothache. 

The  sixth  cranial  nerve  is  called  abducens.  It  leaves  the  cranium  through 
the  anterior  lacerated  (sphenoidal)  fissure.  Paralysis  of  this  nerve  will  cause 
convergent    squint. 

The  seventh  cranial  nerve  is  called  facial.  It  starts  to  leave  the  cranium 
through  the  internal  auditory  meatus  and  after  passing  through  the  aqueduc- 


PLATE  CCXXXV. 


GROOVE  FOR  SUPERIOR  LONGITUDINAL  SINUS 
GROOVE  FOR  ANTERIOR  MENINGEAL  ARTERY 

FORAMEN  CAECUM 
—  CRISTA  GALLI 

SLIT  FOR  NASAL  NERVE 
GROOVE  FOR  NASAL  NERVE 

ANTERIOR  ETHMOIDAL  FORAMEN 
ORIFICES  FOR  OLFACTORY  NERVES 
POSTERIOR   ETHMOIDAL   FORAMEN 

ETHMOIDAL  SPINE 
OLFACTORY  GROOVES 


OPTIC  FORAMEN 

OPTIC  GROOVE 
OLIVARY  PROCESS 
ANTERIOR  CLINOID  PROCESS 
MIDDLE  CLINOID  PROCESS 


POSTERIOR  CLINOID  PROCESS 
GROOVE  FOR  SIXTH  NERVE 
MIDDLE  LACERATED  FORAMEN 
ORIFICE  OF  CAROTID  CANAL 
DEPRESSION  FOR  GASSERIAN  GANGLION 


NTERNAL  AUDITORY  MEATUS 
SLIT  FOR  DURA  MATER 
SUPERIOR  PETROSAL  GROOVE 
FORAMEN  LACERUM  POSTERIUS 
ANTERIOR  CONDYLOID  FORAMEN 
AQUAEOUCTUS   VESTIBULI 

_-  POSTERIOR   CONDYLOID  FORAMEN 


MASTOID  FORAMEN 

-  POSTERIOR  MENINGEAL  GROOVES 


Showing  Foramina  at  the  Base^of  the  Skull. 
440 


ANATOMY  IX  A   NUTSHELL.  441 

tus  Fallopii  it  passes  through  the  stylomastoid  foramen.  This  nerve  may  he 
paralyzed  after  it  leaves  the  stylo-mastoid  foramen,  or  during  its  passage  through 
the  petrous  portion  of  the  temporal  hone,  or  at  its  origin  in  the  brain.  In  any 
of  these  cases  it  is  called  Bell's  paralysis.  Paralysis  of  this  nerve  in  the  brain  is 
also  called   bulbar   paralysis. 

The  eighth  cranial  nerve  is  called  auditory.  It  starts  to  leave  through  the 
internal  auditory  meatus  but  stays  in  the  internal  ear.  One  disease  of  this 
nerve  is  deafness. 

The  ninth  cranial  nerve  is  called  glosso-pharyngeal.  It  leaves  the  cranium 
through  the  middle  compartment  of  the  jugular  foramen.  Loss  of  taste  is 
ageusia. 

The  tenth  cranial  nerve  is  called  pneumogastric.  It  leaves  the  cranium 
through  the  middle  compartment  of  the  jugular  foramen.  One  thing  that  may 
happen  when  this  nerve  does  not  preform  its  function  is  asthma. 

The  eleventh  cranial  nerve  is  called  spinal  accessory.  It  leaves  the  cranium 
through  the  middle  compartment  of  the  jugular  foramen.  Paralysis  of  this 
nerve  causes  spasmodic  torticollis. 

The  twelfth  cranial  nerve  is  called  hypoglossal.  It  leaves  the  cranium 
through  the  anterior  condyloid  foramen.  Paralysis  of  this  nerve  causes  motor 
aphasia. 

The  following  are  the  descriptions  of  those  parts  of  the  brain  not  previously 
given. 

(1)  Valve  of  Yieussens  is  a  thin  leaf  of  medullary  substance  between  the 
superior  peduncles  of  the  cerebellum.  It  is  also  called  anterior  or  superior  medul- 
lary velum. 

(2)  Posterior  or  inferior  medullary  velum  is  the  commissure  of  the 
flocculus  of  the  cerebellum. 

(3)  Posterior  perforated  space  is  the  depression  just  behind  the  cor- 
pora albicantia  at  the  base  of  the  brain.  The  arteries  which  pass  through  this 
space  pass  to  the  optic  thalamus.  It  would  be  better  to  call  it  the  posterior 
perforated  substance. 

(4)  Tuber  cinereum  is  a  tract  of  gray  matter  extending  from  the  optic 
commissure  to  the  corpora  albicantia.  and  it  is  one  of  the  structures  in  the  floor 
of  the  third  ventricle. 

(5)  Lamina  cinerea  is  a  connecting  layer  of  gray  matter  between  the  cor- 
pus callosuin  and  the  optic  commissure.       » 

(6)  Infundibulum  is  a  funnel  shaped  process  of  the  brain  passing  from  the 
tuber  cinereum  to  the  pituitary  body. 

(7)  Corpus  striatum  consists  of  the  caudate  nucleus,  the  lenticular  nucleus. 
and  the  internal  capsule,  and  is  situated  opposite  the  Assure  of  Sylvius. 

(8)  Choroid  plexuses  are  vascular  plexuses  in  the  ventricles  of  the  brain. 

(9)  Tela  choroidea  [nferior  is  the  membranous  pari  of  the  roof  of  the 
fourth  ventricle. 

(10)  Peduncles  of  the  pineal  gland  are  delicate  white  bands  passing 

forward  from  each  side  of  the  pineal  gland  along  the  edge  of  the  third  ventricle 
to  join  the  anterior  pillars  of  the  fornix. 


PLATE  CCXXXVI. 


ANTERIOR  PALATINE  FOSSA  _ 
TRANSMITS  LEFT  NASO-  PALATINE     NERVE 
TRANSMITS     ANTERIOR     PALATINE  VESSEL 
TRANSMITS  RIGHT  NASOPALATINE  NERVE 


ACCESSORY  PALATINE  FORAMINA 


TENSOR     PALATI 

POSTERIOR  NASAL  SPINE 

AZYGOS  UVULAE 

HAMULAR  PROCESS  


SPHENOID     PROCESS  OF  PALATE 
PTERYGOPALATINE  CANAL 

BASILAR  PROCESS 

TENSOR  TYMPANI RECTU! 

PHARYNGEAL  SPINE  FOR.    SITUATION  OF  SUPERIOR  CONSTRICTOR 

EUSTACHIAN  TUBE  AND  CANAL  FOR  TENSOR    TYMPANI 
LEVATOR    PALATI    — — 
CANAL     FOR    JACOBSON S     NERVE 
AQUAEDUCTUS  COCHLEAE  - 

FORAMEN     LACERUM     POSTERIUS 
CANAL  FOR     ARNOLDS     NERVE 

ANTERIOR  CONDYLOID    FORAMEN 
CONDYLE  ARTICULATES  WITh  ATLAS    " —  ORAMEN 

POSTERIOR     CONDYLOID     FORAMEN 


LIGAMENTUM    NUCHAE 


lm;  Inferior  Surfa<  e  of  Base  of  Skull 

442 


ANATOMY  IN  A   NUTSHELL.  443 

(11)  Obex  is  a  band  of  gray  nervous  matter  at  the  point  of  the  calamus 
soriptorius.  The  calamus  scriptorius  is  the  groove  on  the  floor  of  the  fourth 
ventricle,  at  the  end  of  which  is  the  Ventricle  of  Arantius. 

(12)  Ligula  is  the  tongue  shaped  organ  of  white  matter  on  the  lower  part 
of  the  roof  of  the  fourth  ventricle. 

(13)  Fovea  superior  is  a  depression  in  the  floor  of  the  fourth  ventricle 
on  the  outer  side  of  the  eminentia  teres. 

(14)  Fovea  inferior  is  a  depression  with  its  apex  at  the  striae,  which 
cross  the  center  of  the  floor  of  the  fourth  ventricle,  and  its  base  below. 

(15)  Eminentia  teres  is  on  each  side  of  the  median  line  on  the  upper 
half  of  the  floor  of  the  fourth  ventricle.  It  is  produced  by  an  underlying  bundle 
of  white  fibers  (funiculus  teres)  formed  by  fibers  of  the  facial  nerve. 

(16)  Conductor  sonorus  is  formed  by  a  whitish  band  of  fibers  which  are 
connected  below  with  the  strke  medullaris. 

(17)  Ala  cinerea  (trigonum  vagi)  is  a  d<  pr<  ssion  below  the  inferior  fovea. 

(18)  Trigonum  hypoglossi  is  situated  on  the  inner  side  of  the  inferior 
fovea. 

(19)  Tuberculum  acusticum  is  situated  en  the  outer  side  of  the  inferior 
fovea. 

(20)  Fasciculus  unciformis  connects  the  parietal  lobe  with  the  temporal 
lobe,  and  is  situated  in  the  bottom  of  the  fissu'-e  of  Sylvius. 

(21)  Locus  ceruleus    is  a  bluish  depression  above  the  fovea  superior. 


LESSON  CXXXVI. 

The  relations  of  the  External  Carotid  Artery.  (Plates  CXVI- 
CXVII-CXVIII. 

In  Front. — (1)  Skin.  (2)  Superficial  fascia.  (3)  Platysma  and  deep  fascia. 
(4)  Anterior  border  of  Sterno-mastoid,  (•">)  Hypoglossal  nerve,  (6)  Lingual 
vein,  (7)  Facial  vein,  (8)  Digastric  muscle.  (9)  Stylo-hyoid  muscle.  (10) 
Parotid  gland  with  facial  nerve  and  temporo-maxillary  vein  in  its  substance. 

Behind. — (1)  Superior  laryngeal  nerve,  (2)  Stylo-glossus,  (3)  Stylo? 
pharyngeus,   (4)  Glosso-pharyngeal   nerve,   (5)   Parotid   "land. 

Externally. — Internal  carotid  artery. 

[nternally. — (1)  Hyoid  bone,  (2)  Pharynx,  (3)  Superior  laryngeal 
nerve,   (4)   Parotid  gland,   (5)   Ramus  of  jaw. 

The     INTERNAL     CAROTID     ARTERY     (PlaKs     CXVI-CXVII-CXVIII)     which 

begins  at  the  upp<  r  border  of  the  thyroid  cartilage  is  divided  for  convenience 
into  four  parts.  (1)  The  cervical  portion  passes  vertically  upward  in  front  of 
the  transverse  processes  of  the  three  upper  cervical  vertebra?  to  enter  the  car- 
otid canal  in  the  petrous  portion  of  the  temporal  bone.  This  portion  has  no 
branches.  (2)  The  petrous  portion  passes  in  the  carotid  canal  where  it  runs 
forward  and  inward  in  front  of  the  tympanum  and  from  here  ascends  to  the 
cavernous  sinus.  This  portion  gives  off  the  tympanic  branch,  which  runs 
through  a  small  foramen  in  the  wall  of  the  carotid  canal  to  enter  the  tympanum. 
(3)  The  cavernous  portion  passes  in  the  cavernous  sinus  to  the  posterior  clinoid 
process  and  from  here  along  the  body  of  the  sphenoid  bone  and  then  passes 


444 


ANATOMY  IN  A  NUTSHELL. 


upward  on  the  inner  side  of  the  anterior  clinoid  process  where  it  leaves  the  cav- 
ernous sinus.  This  portion  gives  off  (a)  the  artkri.e  receptaculi  branches 
which  pass  to  the  pituitary  body,  Gasserian  ganglion,  and  to  the  walls  of  the 
cavernous  sinus  and  inferior  petrosal  sinus,  (b)  anterior  meningeal  which 
passes  over  the  lesser  wing  of  the  sphenoid  to  the  dura  mater  in  the  anterior 
fossa,  ici  ophthalmic — this  artery  has  been  described  od  page  383,  (4)  The 
cerebral  portion  <nt<  rs  the  fissure  of  Sylvius  and  gives  off  (a)  ANTERIOR  CERE- 
BRAL which  runs  in  the  longitudinal  fissure  around  tin  corpus  callosum  to  its 
posterior  part.      (Plate  CLXXIIL)     Tin:   anterior   communicating   artert 


PLATE  CCXXXVIL 


ARTIC 
PARIETAL 


PACCHIONIAN 

DEPRESSIONS. 


-GROOVES 

FOR  MEN 

1NGEAL 

ARTERIES 


FORAMEN* 
CAICUM. 

ORBITAL  PLATE 

ARTIC  WITH 
MALAR. 

ARTIC  WITH  OS-PLANUM 

ARTIC.  WITH  LACHRYMAL. 
ARTIC.  WITH  MAXILLARY 
ARTIC.  WITH   NASAL. 


NASAL    'SPINE 


ARTIC.  WITH 
GRTR  WING 
3F  SPHENOID. 

ARTIC.  WITH 
ESSER  WING. 

HRYMAL 
FOSSA. 

ETHMOIDAL  NOTCH 

DEPRESSION  FOR  PULLY  OF  SUP  OBLIQUE 

UNDER  SURFACE  OF  NASAL  PROC. 


[nternal  Surface  of  Frontal  Bone. 

joins  tin-  artery  with  its  fellow  near  their  beginning.  This  artery  gives  off  the 
antero-mediarj  ganglionic,  which  passes  through  the  anterior  perforated  space. 
and  lamina  cinerea  to  the  caudate  nucleus  of  the  corpus  striatum.  It  also 
gives  <>\'\  the  antero-internal  frontal,  which  passes  to  the  two  inferior  frontal 
lobes;  ami  the  middle  internal  frontal,  which  passes  to  the  corpus  callosum  and 
i"  the  inner  surface  of  the  ascending  frontal  lobe  and  first  frontal  lobe;  and  it 
finally  gives  off  the  posterior  internal  frontal  which  passes  to  the  quadrate  lobe, 
il.)  MIDDLE  CEREBRAL,  (Plates  CLXXIII-CLXXV)  which  runs  outward  in  the 
fissure  of  Sylvius  and  gives  off  its  branches  near  the  central  lobe.      Its  branches 


ANATOMY  IN  A  NUTSHELL.  445 

are  anterolateral  ganglionic  which  passes  to  the  corpus  striatum,  internal  cap- 
sule and  optic  thalamus;  external  and  inferior  frontal  which  pass  to  the  third 
frontal  convolution;  ascending  frontal  which  passes  to  the  ascending  frontal 
convolution;  the  ascending  parietal  which  passes  to  the  ascending  parietal  con- 
volution; and  parieto-sphenoidal  which  passes  to  the  angular  convolution  and 
the  superior  temporo-sphenoidal  convolution,  (c)  The  posterior  commu- 
nicating artery,  (Plate  CLXXIII)  which  runs  backward  and  joins  the  pos- 
terior cerebral  artery.  It  sends  postero-mediaD  ganglionic  branches  which 
pass  through  the  posterior  perforated  space,  the  optic  thalamus  and  wall  of  the 
third  ventricle,  (d)  Anterior  choroid  artery  which  runs  backward  into 
the  descending  horn  of  the  lateral  ventricle.     (Plate  CLXXIII.) 

The  circle  of  Willis  is  formed  by  seven  arteries  which  make  an  enclosure 
at  the  base  of  the  brain  just  beneath  the  third  ventricle.  All  the  structures 
in  the  floor  of  the  third  ventricle  are  in  the  circle  of  Willis  except  the  tegmental 
portion  of  the  cms,  and  everything  in  the  circle  of  Willis  is  in  the  floor  of  the 
third  ventricle  except  the  optic  commissure.  The  arteries  that  make  this  circle 
arc  the  two  posterior  cerebral  from  the  basilar;  the  two  anterior  cerebral  which 
are  branches  of  the  internal  carotid;  the  two  posterior  communicating  and  the 
anterior  communicating  which  is  the  shortest  artery  in  the  body  and  has  upon 
it  ganglion  of  Ribes. 

The  posterior  cerebral  which  are  branches  of  the  basilar  artery  wind  around 
the  cms  cerebri  to  the  under  surface  of  the  occipital  lobe.     Here  it  sends  branches 

(a)  TO  THE  UNCINATE  LOBE,  (b)  TO  THE  CUNEATE  LOBE,  (c)  TO  THK  TEMPORAL 

lobe.  Xear  its  origin  it  receives  the  posterior  communicating  artery.  The 
postero-median  ganglionic  branches  pass  from  the  posterior  cerebral  through 
the  posterior  perforated  space  to  the  walls  of  the  third  ventricle.  A  posterior 
choroid  branch  conns  from  the  posterior  cerebral  and  passes  to  the  velum  in- 
terpositum  and  choroid  plexus.  A  postero-Iateral  ganglionic  branch  comes 
from  the  posterior  cerebral  ami  passes  to  the  optic  thalamus. 


LESSON  CXXXVII 

The  Relations  of  the  Entern  kl  Carotid  Artery. 

Ix  Front.  —  (1)  Skin,  (2)  Superficial  ami  deep  fascia,  (3)  Platysma,  (4) 
Sterno-mastoid,  (5)  Occipital  artery,  (0)  Posterior  auricular  artery.  (7)  Hypo- 
glossal nerve,  (8)  Parotid  gland,  (9)  Stylo-glossus,  (10)  Stylo-pharyngetis. 
(11)  Glosso-pharyngeal  nerve,  (12)   Pharyngeal  branch  of  the  pneumogastric. 

Behind. — (1)  Rectus  capitis  amicus  major.  (2)  Sympathetic,  (•'>)  Super- 
ior laryngeal  nerve. 

Externally. — (1)   Internal   jugular  vein,    (2)    Pneumogastric   nerve. 

Internally. — (1)  Pharynx,  (2)  Superior  laryngeal  nerve.  (3)  Ascending 
pharyngeal   artery,    (4)  Tonsil. 

The  Right  subclavian  artery  arises  from  the  innominate  opposite  the  sterno- 
clavicular articulation  and  passes  upward  and  outward  to  the  Scalenus  anticus 
muscle  on  the  right  side.  The  left  Subclavian  artery  arises  from  the  end  of 
the  arch  of  the  aorta  and  ascends  to  the  Scalenus  anticus  muscle.      The  artery 


440 


W  ATOMY  IX  A   XI  TSHELL. 


now  runs  outward  behind  the  Scalenus  anticus  muscle  then  downward  under 
the  clavicle  to  the  lower  border  of  the  first  rib  where  it  takes  the  name  of  axil- 
lary. 'Hit'  Scalenus  anticus  muscle  divides  this  artery  into  three  portions. 
The  portion  internal  to  the  muscle  is  the  first  portion,  the  portion  behind  it  is 
;Ik   second  portion,  and  the  portion  <  xternal  to  it  is  the  third  portion. 

'I'm:  Relations  of  First  Portion  ok  the  Right  Subclavian  Artery. 
1\  Front. — (1)  Skin.  (2)  Superficial  fascia.  (.'!)   Platysma  and  deep  fascia, 
l     Clavicular  origin  of  Sterno-mastoid,  (5)  Sterno-hyoid,  (6)  Sterno-thyroid, 
(7)  Anterior   jugular,    (8)   Internal   jugular,    (9)  Vertebral   veins,    (10)   Pneu- 

PLATE  CCXXXVIII. 


METOPIC 
SUTURE. 


FRONTAL 
%%      EMINENCE 


SUPERCILIARY     Wk' 
RIDGE. 

0BICULAR1S  PALPEBRARUM.' 

INT.  ANGULAR  PROC 


SUPRAORBITAL 
NOTCH  OR  FORAMEN. 

CORRUGATOR  SUPERCILII. 


NASAL  SPINE. 


Extern  \i.  Surface  of  Frontal  Bone. 

mogastric  nerve,  (11)  Cardiac  nerves,  (12)   hoop  from  the  sympathetic. 

Behind.     (1)   Recurrent  laryngeal  nerve,  (2)  Sympathetic,  (3)   Pleura 
i  1 1   Apex  of  lung. 

Beneath.— (1)   Pleura,    (2)   Recurrent    laryngeal   nerve. 

Tin:  Relations  of  First  Portion  ok  Left  Subclavian  Artery. 

In  Front.  (1)  Pneumogastric  nerve,  (2)  Cardiac  nerves,  (3)  Phrenie 
nerve,  (4)  Left  carotid  artery.  (5)  Thoracic  duct,  ((i)  Left  internal  jugular. 
(7i  Vertebral  vein,  (8)  Innominate  vein,  (9)  Sterno-thyroid.  (10)  Sterno- 
hyoid, (11)  Sterno-mastoid. 

Behind.     (1)  Oesophagus,  (2)  Thoracic  duct.  (.'-!)   Inferior  cervical  gang- 


ANATOMY  IN  A  NUTSHELL.  447 

lion  of  sympathetic,  (4)  Longus  colli. 

Outer  Bide. — (1)  Pleura,   (2)  Left  lung. 

Inner  Side. — (1)  Trachea.  (2)  (Esophagus, (3)  Thoracic  duct. 


LESSON  CXXXVIII. 
The  Relations  of  Second  Portion  of  Subclavian  Artery  are  the  same 

on  each  side. 

In  Front. — (1)  Skin,  (2)  Superficial  fascia,  (3)  Platysma  and  deep  cer- 
vical fascia,  (4)  Sterno-mastoid,  (5)  Phrenic  nerve,  (6)  Scalenus  auticus. 
'  7)   Subclavian  vein. 

Behind. — (1)   Pleura,    (2)  Scalenus  medius. 

Aboate. — Brachial  plexus. 

Below. — Pleura. 

The  Relations  of  Third  Portion  of  Subclavian  Artery  are  the  same 
on  each  side. 

In  Front. — (1)  Skin,  (2)  Superficial  fascia,  (3)  Platysma  and  deep  cer- 
vical fascia,  (4)  Descending  branches  of  cervical  plexus,  (5)  Nerve  to  sub- 
clavius  muscle,  (6)  Subclavius  muscle,  (7)  Suprascapular  artery,  (8)  Supra- 
scapular vein,  (9)  The  external  jugular  vein,  (10)  Transverse  cervical  vein. 
(11)  Clavicle. 

Behind. — (1)   Scalenus  medius,  (2)    Lower  cord  of  brachial  plexus. 

Above. — (1)  Brachial  plexus,  (2)  Omo-hyoid  muscle. 

Below. — First  rib. 


LESSON  CXXXIX. 

The  branches  of  the  subclavian  artery  are  (1)  vertebral,  which  arises  at 
the  upper  and  back  part  of  the  artery  and  passes  upward  through  the  foramina 
in  the  transverse  processes  of  the  upper  six  cervical  vertebrae.  After  it  passes 
through  the  foramen  in  the  transverse  process  of  the  atlas,  it  passes  behind  the 
articular  process  of  this  bone  in  the  sinus  atlantis  lying  superficial  to  the  sub- 
occipital nerve.  11  now  pierces  the  dura  mater  and  passes  through  the  torn  men 
magnum  of  the  occipital  bone  to  the  front  of  the  medulla  oblongata. 

It  unites  with  the  opposite  vertebral  at  the  low<  r  border  of  the  pons  to  form 
the  basilar  artery.  The  branches  of  the  vertebral  artery  are:  (A)  the  cer- 
vical branches  which  send  muscular  branches  to  the  neck,  lateral  spinal 
which  pass  through  the  intervertebral  foramen  and  then  divides  into  two 
branches  one  of  which  runs  along  the  nerve  roots  to  the  cord  and  its  coverings, 
the  other  divides  into  ascending  and  descending  branches  which  form  with 
similar  branches  from  above  and  below  loops  on  the  posterior  surfaces  of  the 
bodies  of  the  vertebrae.  (B)  cranial  branches  which  send  posterior  menin- 
geal branches  to  the  posterior  fossa,  anterior  spina!  descends  in  front  of  the 
medulla  and  unites  with  its  fellow  to  form  a  single  trunk  at  the  foramen  mag- 
num. This  main  branch  descends  in  the  anterior  median  fissure  of  the  cord. 
For  description  of  anterior  spinal  and  posterior  spina!  see  page  337.  The  pos- 
terior inferior  cerebellar  is  tin-  last  branch  of  this  crania]  portion  and  winds 
around  the  medulla  across  the  restiform  body  to  the  under  surface  of  the  cere- 
bellum. 


lis 


ANATOMY  IN  A  NUTSHELL 


These  two  vertebral  arteries  unite  to  form  the  basilar  artery,  which  runs 
in  a  groove  in  the  middle  of  the  pons  to  its  anterior  border  where  it  divides  into 
the   posterior  cerebral   branch.     The   basilar  artery  gives  off   (A)  numerous 

TRANSVERSE     BRANCHES    to    the    polls    and    adjacent    parts,    (B)    THE    INTERNA! 

\i  [>n<n;v    v.rtery  which  runs  with  the  auditory  uerve  in  the  internal  meatus 

> 

(C)  the  anterior  inferior  cerebellar  artery  which  crosses  the  cms  cere- 
belli  to  the  anterior  border  of  the  under  surface  of  the  cerebellum,  (D)  the 
51  perior  cerebellar  which  winds  abound  the  crus  cerebri  on  each  side  near 
the  fourth  uerve  to  reach  the  upper  surface  of  the  cerebellum. 

PLATE  CCXXXIX. 


ANT.  SUP. 
ANGLE. 


POST.SUF. 
ANGLE 


POST.  INF 
ANCLE. 


FOR  LATERAL 
SINUS. 


-GROOVES  FOR 
ODLE  MENINGEAL, 
ARTERY. 


ANT.  INF. 
ANGLE. 


[nternal  Surface  of  the  Parietal  Bone. 

(2)  The  internal  mammary  arises  from  the  first  portion  of  the  subclavian 
artery  opposite  the  thyroid  axis  and  descends  on  the  posterior  surfaces  of  the 
costal  cartilages  to  the  sixth  interspace  where  it  divides  into  the  musculo* 
phrenic  and  the  superior  epigastric  branches.  As  it  passes  down  it  is  about  a 
half  an  inch  fromthe  sternal  margin.  The  branches  of  the  internal  mammary 
are  (a  i  COMES  \Kuvi  phrenici  which  accompanies  the  phrenic  nerve  to  the 
Diaphragm,  (b)  the  mediastinal  branch  which  passes  to  the  anterior  med- 
iastinum, (c)  pericardiac  which  passes  to  the  anterior  surface  of  the  pericardium, 

(d)  sternal   branches   which   pass  to   the  posterior  surface  of  the  sternum, 

(e)  interior  [ntercostal  branches  which  pass  to  the  five  or  six  upper  in- 
terspaces where  each  branch  divides  inio  two  divisions  to  pass  along  the  mar- 


\\  \TOMY  IX  A  NUTSHELL.  449 

gins  of  the  interspaces,  (f)  perforating  branches  which  pass  through  the 
five  or  six  upper  interspaces  to  the  skin  and  muscles  on  the  chest,  and  those 
that  pass  through  the  second,  third,  and  fourth  spaces  go  to  the  mammary 
gland. 

Of  its  terminal  branches  the  musculo-phrenic  runs  behind  the  cartilages 
of  the  false  ribs  to  pierce  the  Diaphragm  at  the  eighth  or  ninth  rib  and  ends  at 
the  twelfth  rib  where  it  gives  off  anterior  intercostals  to  the  lower  intercostal 
spaces   pericardiac  branches,  and  diaphragmatic  branches. 

Its  other  terminal  branch  the  superior  epigastric  descends  in  the  interval 
between  the  sternal  and  costal  attachments  of  the  Diaphragm  to  pierce  the 
sheath  of  the  Rectus  muscle  running  on  its  posterior  surface  to  anastomose 
with  the  deep  epigastric  in  the  substance  of  this  muscle. 


LESSON  CXL. 

(3)  The  thyroid  axis  arises  near  the  the  Scalenus  Anticus  from  the  first 
portion  of  subclavian  artery  and  gives  off  inferior  thyroid,  suprascapular, and 
trans versalis  colli  arteries. 

The  inferior  thyroid  artery  ascends  behind  the  middle  cervical  ganglion  of 
the  sympathetic  and  the  sheath  of  the  common  carotid  artery  to  the  thyroid 
gland.  It  crosses  the  vertebral  artery,  Longus  colli  muscle,  and  the  recurrent 
laryngeal  nerve.  It  may,  however,  pass  under  this  nerve.  Its  branches  are, 
(a)  tracheal,  which  pass  to  the  trachea,  (b)  oesophageal,  which  pass  to  the 
oesophagus,  (c)  muscular,  which  pass  to  the  adjacent  muscles,  (d)  inferior 
laryngeal,  which  passes  to  the  back  of  the  larynx  with  the  recurrent  laryn- 
geal nerve,  (e)  ascending  cervical,  which  passes  between  the  Scalenus  an- 
ticus muscle  and  the  Rectus  capitis  anticus  major  on  the  anterior  tubercles  of 
the  transverse  processes. 

The  suprascapular  artery  crosses  the  Scalenus  anticus  muscle  behind  the 
clavicle  and  passes  over  the  transverse  ligament  of  the  scapula  to  the  supra- 
spinous and  infraspinous  fossa?.  This  artery  goes  to  the  clavicle,  scapula,  and 
humerus,  as  well  as  to  the  sterno-clavicular  articulation  and  acromio-clavicu- 
lar  articulation  and  the  shoulder  girdle. 

The  transversalis  colli  is  on  a  higher  level  than  the  suprascapular  artery  and 
crosses  the  Scaleni  muscles  and  the  brachial  plexus  to  the  Trapezius  muscle. 
Here  it  divides  two  branches,  (a)  superficial  cervical  which  ascends  under 
the  anterior  border  of  the  Trapezius  to  anastomose  with  the  superficial  branch 
of  the  arteria  princeps  cervicis,  (b)  tiiio  posterior  SCAPULAR  branch,  which 
runs  under  the  Levator  anguli  scapulae  to  the  superior  angle  of  the  scapula  and 
then  descends  under  the  Rhomboidei  muscles  to  the  inferior  angle  of  the  scapula. 
This  artery  may  arise  from  the  third  portion  of  the  subclavian. 

(4)  The  superior  intercostal  comes  from  the  upper  and  hack  pari  of  the 
subclavian  artery  and  descends  on  the  neck  of  the  first  two  ribs  to  supply 
the  first  two  intercostal  spaces.  In  the  first  intercostal  space  it  gives  off  a 
branch  which  is  distributed  in  like  manner  to  the  aortic  intercostals.  The 
artery  in  the  second  intercostal  space  generally  joins  one  from  the  highest 
aortic   intercostal.      All    intercostal   arteries  give  off  branches   to   the   posterior 


450 


ANATOMY  IX  A  NUTSHELL. 


spinal  muscles  and  a  small  one  which  passes  to  the  spinal  cord  and  its  mem- 
brane. The  profundus  cervicis  most  always  comes  from  the  superior  inter- 
costal, but  it  may  come  from  the  subclavian  artery  itself.  It  ascends  under 
the Complexus  muscle  as  far  the  axis  to  anastomose  with  the  deep  branch  of  the 
arteria   princeps  cervicis. 

The  relation—  of  the  thoracic  aorta  are  given  on  page  286.  and  its 
branches  arc  (1)  pericardiac,  which  are  small  arteries  and  are  distributed  To 
the  pericardium.  (2)  the  bronchial  arteries  are  nutrient  arteries  to  the  lungs. 
The  one  on  the  right  side  may  come  (A)  from  the  first  aortic  intercostal, 


PLATE  CCXL. 


PARITTAL 
FORAMEN. 


TEMPORAL 

R,DGES-    jurtu  :^*~ 


ART,LT'5  Wl 
SPHENOID. 


SQUAMOUS  PORTION, 
TEMPORAL  MUSCLE. 
■^-EMINENCE. 


MASTOID 
PORTION- 


External  Surface  of  the  Parietal  Bone. 


(B)    IT    MAY  COME  BY  A  COMMON  TRUNK  WITH  THE  LEFT  BRONCHIAL  which  collies 

from  the  fronl  of  the  thoracic  aorta.  There  are  generally  two  on  the  left  side. 
These  arteries  nourish  the  bronchial  tubes,  the  cellular  tissue  of  the  lungs,  the 
bronchial  glands,  and  the  (esophagus,  (3)  (Esophageal  arteries  are  generally 
four  or  five  in  number,and  come  from  the  front  of  the  thoracic  aorta  and  pass  ob- 
liquely to  the  oesophagus.  Above  they  anastomose  with  the  inferior  thyroid 
arteries,  ami  below  with  branches  from  the  phrenic  and  gastric  arteries.  (4) 
The  posterior  mediastinal  arteries  are  small  arteries  which  supply  the  glands  in 
the   posterior  mediastinum. 


ANATOMY  IN  A  NUTSHELL.  451 

LESSON  CXLI. 

(5)  The  intercostal  arteries  are  eleven  in  number.  Those  of  the  first  and 
second  spaces  come  from  the  subclavian,  and  the  remaining  nine  come  from  the 
thoracic  aorta.  The  last  one,  which  passes  along  the  lower  border  of  the  Last 
rib,   is   called  the   subcostal. 

The  right  intercostal  arteries  are  longer  than  the  left  ones  because  the 
aorta  is  situated  on  the  left  side  of  the  spine.  In  each  intercostal  space  the 
artery  lies  upon  the  External  intercostal  muscle  and  has  in  front  of  it  the  pleura 
and  a  thin  fascia.  From  here  it  passes  between  the  two  layers  of  intercostal 
muscles  and  passes  to  the  lower  border  of  the  rib  above  to  pass  forward  in  the 
groove  on  the  lower  border  of  this  rib  to  anastomose  with  the  anterior  inter- 
costals  which  are  branches  of  the  internal  mammary.  The  first  intercostal, 
which  comes  from  the  aorta,  anastomoses  with  the  superior  intercostal,  while 
the  last  three  intercostals  which  come  from  the  aorta  pass  between  the  abdom- 
inal muscles  to  anastomose  with  the  epigastric  in  front  and  with  the  phrenic 
and  lumbar  arteries  behind.  In  each  intercostal  space  there  is  a  vein,  artery, 
and  nerve,  and  their  position  from  above  down  is  vein,  artery,  and  nerve,  ex- 
cept in  the  upper  intercostal  spaces  where  the  nerve  is  first  above  the  artery. 
Fibrous  arches  keep  the  intercostal  muscles  from  pressing  upon  the  intercostal 
arteries  during  respiration.  The  lower  intercostal  arteries  pass  into  the  ab- 
dominal wall  and  into  the  sheath  of  the  Rectus  muscle  where  they  anastomose 
with  the  internal  mammary  and  the  deep  epigastric  artery.  The  branches  of 
the  intercostal  arteries  are  (a)  the  posterior  or  dorsal  branch,  which  passes 
backward  to  the  inner  side  of  the  anterior  costo-transverse  ligament  where  it 
is  distributed  to  muscles  and  integument  of  the  back  after  dividing  into  an  ex- 
ternal and  internal  branch,  (b)  The  spinal  branch,  which  passes  through 
the  intervertebral  foramen  to  be  distributed  to  the  spinal  cord  and  its  coverings 
and  the  bodies  of  the  vertebrae,  (c)  The  collateral  intercostal  branch 
arises  from  the  intercostal  artery  close  to  the  angle  of  the  rib  and  then  passes 
downward  to  the  upper  border  of  the  rib  below,  along  which  it  passes  to  anas- 
tomose with  the  anterior  intercostals  from  the  internal  mammary. 

The  thoracic  aorta  commences  on  a  level  with  the  fourth  dorsal  vertebra 
and  descends  on  the  left  side  of  the  spine  to  pass  through  the  abdominal  open- 
ing in  the  Diaphragm  after  which  it  is  called  abdominal  aorta. 

The  abdominal  aorta  commences  at  the  aortic  opening  in  the  Diaphragm 
extends  to  the  front  of  the  body  of  the  fourth  lumbar  vertebra  where  it  divides 
into  tiih  right  and  lkft  common  iliac  arteries.     (Plate  XCI  | 


LESSON  CXLI  I. 
The  Relations  of  the  Abdominal  Aorta. 
In    Front. — (1)  Lesser    omentum,    (2)  Stomach.    (3)   Branches    of    the 
cceliac  axis,   (4)  Solar  plexus,   (5)  Splenic  vein,   ((>)   Pancreas,   (7)    Left    renal 
vein,  (8)  Transverse  duodenum,  (9)  Mesentery,  (10)   Aortic  plexus. 
Behind. — (1)   Left    lumbar   veins,    (2)   Vertebral    column. 
Right  Side. — (1)  Right  cms  of  Diaphragm,  (2)    Inferior  vena  cava,  (3) 
Yena  azygos  major,  (4)  Thoracic  duct,  (5)   Right  semilunar  ganglion. 


452 


ANATOMY  IN  A  NUTSHELL. 


Left  Side. — (1)  Left  lumbar  veins.  (2)  Left  semilunar  ganglion. 

The  branches  of  the  abdominal  aorta  are  (1)  parietal  branches  and  under 
this  we  have  (A)  phrenic  branches  which  are  two  in  number  and  as  a  rule 
arise  close  together  on  the  under  surface  of  the  Diaphragm,  but  they  present 


PLATE  CCXLI. 


A-0CCIP1T0  FRONTALIS. 

B-TRAPEZIUS. 

C-STERNO-  MASTOID 

D-SPLENIUS 

E-COMPLEXU! 

F-0BL'Q5.SUR 

G  -  RECTU  S 

CAPITUS 

POST.  Ml 
H-NECTUS 

CAPIT 

POST.MIN. 
I  -  RECTU5- 

CAP.LAT. 

J-FEC-CAB/I 

K-RECCftP.AJfT.MJ. 

L-SURCONSTRICTO 

M- POST.  CONDYLOID 
FORAMEN. 

N- ANT.  CONDYLOID  FORAMEN. 


0-  SUP.  CURVED  OR  NUCHAL  LINE. 

P-  LINEA  SUPREMA. 

Q- INF.  CURVED  LINE. 

R-FOR  LIGAMENTUM 
NUCHAL. 

^■%    S  -  INION  OR  EXT. 
%a       OCCIPITAL 
^  .„      PROTUB- 
ERANCE. 
T- CREST. 

U-BAS- 
&    ILAR 
PROC 

V- PHAR- 
YNGEAL 
SPINE. 

-TUBERCLES 

FOR  CHECK 

LIGAMENTS 

X- JUGULAR  PROC. 
Y-  CONDYLES.  ART.WITH  ATVS. 


External  Surface  of  Occipital  Bone. 

much  variation  in  their  origin  since  they  may  come  by  a  common  trunk  or  one 
may  come  from  the  comae  axis  and  the  other  from  the  renal  artery.  The  one 
on  the  righl  side  passes  across  the  crura  of  the  Diaphragm  to  the  under  surface 
of  that  muscle  behind  the  inferior  vena  cava,  while  the  one  on  the  left  side  passes 
behind  the  oesophagus  to  the  under  surface  of  the  Diaphragm.  (B)  Ltjmbab 
arteries  are  five  pairs  and  arise  from  the  back  of  the  aorta  to  pass  outward 
on  the  body  of  the  vertebrae  beneath  the  Psoas  magnus  muscle  and  the  sympathe- 
tic nerve.  The  first  two  pairs  pass  under  the  crura  of  the  Diaphragm  and  the 
right  one  also  passes  under  the  inferior  vena  cava.  Near  the  transverse  pro- 
cesses of  the  vertebrae  they  divide  into  an  abdominal  branch,  which  passes 
outward  beneath  the  Quadratus  lumborum  to  end  between  the  muscles  of  the 
abdominal  wall  where  they  anastomose  with  the  deep  epigastric,  the  internal 
mammary,  the  ilio-lumbar,  and  the  circumflex  iliac  arteries.     It  is  well  to  say 


ANATOMY  IN  A  NUTSHELL.  453 

that  the  first  pair  cross  the  Quadratus  lumborum  muscle.  The  other  branch  is 
the  dorsal  branch  which  passes  with  the  posterior  primary  branch  of  the  inter- 
costal nerve  and  gives  off  spinal  branches  which  supply  the  spinal  cord  and  its 
coverings.  It  anastomoses  with  the  intercostal  artery.  (C)  Sacramedia  is 
a  small  branch  given  off  at  the  bifurcation  of  the  abdominal  aorta  and  passes 
over  the  fifth  lumbar  vertebra  and  the  sacrum  to  the  coccyx  where  it  anasto- 
moses  with  the  lateral  sacral  arteries.     (Plate  XC.) 


LESSON  CXLIII. 
(2)  The  visceral  branches  and  under  these  we  have  (A)  coeliac  axis,  which 
is  a  short  trunk  about  a  half  of  an  inch  long,  arises  between  the  crura  of  the 
Diaphragm  just  above  the  Pancreas.  It  passes  horizontally  forward  and  di- 
vides into  three  branches.  Gastric  or  coronary  artery  is  the  smallest  of  these 
three  branches  and  passes  upward  to  the  left  side  behind  the  lesser' sac  of  the 
peritoneum  to  the  cardiac  end  of  the  stomach.  It  also  uives  branches  to  the 
oesophagus,  then  turns  to  the  right  and  passes  along  the  lesser  curvature  of  the 
stomach  sending  branches  to  both  sides  of  the  stomach.  It  anastomoses  with 
the  pyloric  branch  of  the  hepatic  artery.  Hepatic  artery  passes  forward  and 
upward  between  the  layers  of  the  lesser  omentum  to  the  transverse  fissure  in 
the  liver  where  it  divides  into  right  and  left  hepatic  branches  to  supply  the 
lobes  of  the  liver.  In  the  fetus  this  is  the  largest  of  the  branches  of  the  cceliac 
axis  because  it  supplies  the  liver  which  is  such  a  large  organ  in  the  fetus.  In 
the  adult  this  artery  is  smaller  than  the  splenic  artery.  The  branches  of  the 
hepatic  artery  are  Pyloric,  which  extends  along  the  lesser  curvature  of  the 
stomach  passing  from  right  to  left  to  anastomose  with  the  gastric  artery.  ( i.\^- 
tro-duodenalis  pass  behind  the  first  portion  of  the  duodenum  and  divides 
into  the  folio  whig  branches.  Gastro-epiploiea  dextra,  which  runs  along  the 
greater  curvature  of  the  stomach  from  right  to  left  to  anastomose  with  the 
gastro-epiploiea  sinistra  which  is  a  branch  of  the  splenic  artery.  This  artery 
gives  branches  to  both  the  stomach  and  the  great  omentum.  Pancreatico- 
duodenalis  superior  passes  between  the  second  part  of  the  duodenum  and  the 
pancreas.  After  supplying  both  of  these  organs,  it  anastomoses  with  the  pan- 
creatico-duodenalis  inferior  which  is  a  branch  of  the  superior  mesentery  and 
with  the  pancreatic  branches  of  the  splenic.  The  right  hepatic  passes  to  the 
righl  lobe  of  the  liver  ami  uives  off  the  cystic  artery  which  supplies  the  gall 
bladder.  The  left  HEPATIC  passes  to  the  left  lobe  of  the  Liver  and  uives  off 
branches  to  the  Spigelian  lobe  .  The  splenic  artery  is  the  largest  of  the  three 
branches  of  the  cceliac  axis  and  is  very  tortuous  in  its  course.  It  passes  along 
the   upper   border  of   the    pancreas,    crosses    the   left    kidney    to    the   spleen.       It 

divides  into  pancreatic^  i'\i;\  e.     These  pancreatic  branches  supply  the  upper 

border  of  the  pancreas  while  Tin;  PANCREATN  \  MAGNA,  which  is  :i  single  large 
branch,  passes  from  the  left  to  the  right  near  the  posterior  surface  of  the  pan- 
creas accompanying  the  pancreatic  duct.  Tun  GASTRIC  BRANCHES,  called 
vasa   BREVIA,  are    live   or  >i\    in  number  and  pass  to  the  left   extremity  of   the 

stomach  which  it  supplies.  Gastroepiploic*  sinistra  is  the  Largesl  o\'  the 
branches  of  the  splenic  artery  and  runs  from  left  bo  right  along  the  greater  cur- 


454 


ANATOMY    IN   A   NUTSHELL. 


vature  of  the  stomach  between  the  layers  of  the  great  omentum.  It  anasto- 
moses with  the  gastro-epiploica  dextra  and  supplies  both  the  greater  omentum 
and  the  stomach.  (B)  Superior  mesentery  arises  about  one-fourth  of  an  inch 
below  the  cceliac  axis  and  passes  between  the  pancreas  and  the  third  portion 
of  the  duodenum  which  it  crosses  and  passes  downward  to  the  right  be+  ^en 
the  layers  of  the  mesentery.  It  supplies  all  of  the  small  intestine,  except  the 
first    portion   of  the  duodenum.     It  also  supplies  the  caecum,  the  ascending 


PLATE  CCXLII. 


FOR  FALX  CEREBELLI. 


FOUFALX  CEREBRI 


TORCULAR 
HEROPHILI. 


POST  CONDYLOID 
FORAMEN. 


LATERAL  SINUS 
ANT  GONDYLOID  FORAMEN 
FOR    PETROSAL  SINUS. 


JUGULAR    FOSSA. 
GROOVE  FOR  MEDULLA. 

BASILAR  PROC. 


Internal  Surface  of  Occipital  Bonk. 

colon,  the  transverse  colon.  Its  branches  are  pancreatico-duodenalis  in- 
ferior, which  passes  from  Left  to  right  in  the  concavity  of  the  duodenum  where 
ii  anastomoses  with  the  pancreatico-duodenalis  superior.  It  gives  branches  to 
the  head  of  the  pancreas  and  to  the  transverse  and  descending  portions  of  the 
duodenum.     Vasa   entestini  tenuis   are  twelve  or  fifteen  in  number  which 

c •  from  the  left  convex  side  of  the  superior  mesenteric  artery  to  supply  the 

jejunum  and  ileum.  Aboul  two  inches  from  their  origin  each  branch  divides 
and  joins  similar  branches  from  the  adjacent  artery  thus  forming  arches  from 


ANATOMY    IN    A    NUTSHELL. 


455 


which  numerous  branches  are  given  off  to  supply  the  mesentery  and  the  small 
intestine.  Four  or  five  sets  of  arches  are  given  off.  The  ilio-colic  artery 
is  given  off  from  the  right  side  of  the  superior  mesentery  artery.  It  passes  be- 
tween the  layers  of  the  mesentery  to  the  right  iliac  fossa  where  it  divides  into 
two  -anehes,  ascending  and  descending.  The  ascending  one  passes  to  the 
ascending  colon  and  anastomoses  with  the  colica-dextra.  The  descending  one 
passes  to  the  lower  part  of  the  ileum,  csecum.  appendix,  and  ileo-csecal  valve. 
The  colica-dextra  arises  from  the  middle  of  the  superior  mesentery  artery 
and  passes  behind  the  peritoneum  to  the  ascending  ion  where  it  gives  off  an 
ascending  branch  which  anastomoses  with  the  colica-media.  and  a  descending 
branch  which  anastomoses  with  the  ileo-colic.  Colica-media  comes  from  the 
upper  part  of  the  concavity  of  the  superior  mesenteric  artery  and  passes  for- 

PLATE  CCXLIIL 


LESSER  WING. 


1  -  ANT.CLINOIO 
PROCESS 


2  -  MID.  CLINOIO 

PROC 

3  -  POSTCLINOID  PROC 
4 -OPTIC  GROOVE 
5-- OLIVARY  PROC. 

6  -  SELLA  TURCICA. 

7  -  CAVERNOUS  GROOVE 
8-LINGULA 
9 -SPINOUS  PROC. 


\/\  SUPP0RT5 
PTERYGOI 


GRqOVE  FOR  OLFACTORY  TRACT.  C  REATER  WING 


10- FORAMEN 

OPTICUM. 

II-  GROOVE  FOR 

SIXTH  WTRVE. 

12 -SPHENOIDAL 
FISSURE. 
13- FORAMEN 

VESALII. 
H-  FORAMEN  OVALE 
15-  FORAMEN 


'X-'l  SPINOSUM. 

1/    16- FORAMEN  ROruNDUM 


Posterior  View  of  the  Sphenoid  Bom:. 

ward  in  the  transverse  meso-colon  where  it  givi  s  a  right  branch  which  anas- 
tomoses with  the  colica-dextra,  and  a  left  branch  which  anastomoses  with  the 
colica-sinistra.  ((')  (Plate  CLVII.)  The  inferior  mesentery  artery  arises  from 
the  left  side  of  the  aorta  aboul  an  inch  and  a  half  above  the  bifurcation.  It 
supplies  the  descending  colon,  sigmoid  flexure,  and  the  greater  part  of  the  rec- 
tum. It  lies  a1  hist  on  the  left  side  of  the  abdominal  aorta,  then  crosses  the 
Psoas  muscle,  left  common  iliac  artery,  ami  un  ter,  to  the  back  of  the  rectum. 
It  gives  off  the  following  branches.  COLU  \->i\i>ti;  \. which  passes  behind  the 
peritoneum  upward  in  front  of  the  left  kidney  to  th<  descending  colon  where  it 
divides  into  an  ascending  branch,  which  anastomoses  with  the  colica-media, 
and  a  descending  branch  which  anastomoses  with  the  sigmoid  artery  and  the 
superior  hemorrhoidal  artery.  Tin:  sigmoid  lrteri  passes  to  the  sigmoid 
flexure  and  anastomosi  s  with  the  colica-sinisl  ra  and  the  superior  haemorrhoidal. 


156 


ANATOMY    IN    A    NUTSHELL. 


The  SUPERIOB  hemorrhoidal  artery  is  really  a  continuation  of  the  inferior 
mesenteric  artery  and  passes  behind  the  rectum  to  divide  into  two  branches  in 
the  meso-rectum.  One  branch  passes  od  cither  side  to  within  about  six  inches 
oi  the  anus  where  they  subdivide  to  supply  the  rectum.  This  artery  anasto- 
moses with  the  sigmoid,  middle  and  inferior  haemorrhoidal  arteries.  (D)  The 
suprarenal,  sometimes  called  middle  capsular,  are  two  in  number  and  come 
from  the  abdominal  aorta  a  little  below  the  cceliac  axis.  They  pass  obliquely 
upward  and  outward  over  thecrura  of  the  Diaphragm  to  the  suprarenal  body. 
They  anastomose  with  the  superior  capsular  of  the  phrenic  and  the  inferior 
capsular  of  the  renal.     (E)  The  renal  arteries  are  two  in  number  which  come 

PLATE  CCXLIV. 


SPHENOIDAL  FISSURE,  OPTIC  FORAMEN    ARTIC.  WITH  PERPEND'R  PLATE-  ARTIC.  WITH  MALAR. 


TEMP'L  FOSSA 

ORB  [TAL  SURFACE 

PTERYGOID  RIOGE. 

ZYGOMATIC  FOSSA 

+   SPHENODAL 
TURBINAL  BONES 


W\(<k  Fn'ERYG0  WL\1  GROOVE  FOR 
U   |«  ATINE  CANAL.   ALA  OF  VOMER 

'     VAGlNALPf?0CLROSTRUM. 

*  ARTIC. WITH  VOMER. 


PTERYGOIO  PLATES   EXT.     yIN"D 


HAMULAR  PROCESSES 


{,\     TEMPORAL. 

EXT.  PTERYGOID. 
FORAMEN  ROTUNDUM 
VIDIAN  CANAL. 
SPINOUS  PROC. 

FORAMEN  SPJNOSUM. 


NOTCH . 


Anterior  View  of  Sphenoid  Bone. 

from  tin  abdominal  aorta  about  a  half  an  inch  below  the  superior  mesenteric. 
The  one  on  the  righl  side  is  a  little  lower  than  the  one  on  the  left  side  because 
the  kidney  is  a  little  lower.  Each  passes  outward  to  supply  the  kidney.  The 
righl  one  passing  behind  the  inferior  vena  cave.  As  they  enter  the  kidney 
each  divides  into  four  or  five  branches.  A  plexus  of  nerves  accompany  this 
artery,  [t  supplies  branches  to  the  suprarenal  body,  ureter,  and  the  surround- 
ing fa1  and  muscles.  Som<  times  th<  re  is  a  second  renal  artery.  At  the  hilum 
of  the  kidney  the  position  of  the  structures  from  before  backward  are  vein, 
.   and    ii"  (F)   The  spermatic  arteries  are  t wo  small   arteries   which 

arise  jusl  b<  low  the  renal  arteri<  s  from  the  abdominal  aorta.  They  pass  down- 
ward and  outward  behind  the  peritoneum  but  over  the  Psoas  magnus  muscle 
and  ur<  ter  and  external  iliac  artery,  the  one  on  the  right  side  also  crosses  the 
inferior  vena  cava)  to  the  internal  abdominal  ring.  Here  they  pass  with  the 
spermatic  vein-  and  spermatic  plexuses  and  vas  deferens  through  the  inguinal 
canal  t<>  puss  out   the  i  xternal  abdominal  ring  into  the  scrotum  where  it  sup- 


ANATOMY    IN    A    NUTSHELL. 


457 


plies  the  testicle.  Each  artery  anastomoses  with  the  artery  of  the  vas  deferens 
and  the  cremasteric  artery.  In  the  female  these  arteries  are  called  the  ovarian. 
They  are  shorter  than  the  spermatic  and  do  no1  pass  out  of  the  abdominal  cav- 
ity. They  rim  between  the  layers  of  the  broad  ligament  of  the  uterus  to  the 
ovary  and  the  round  ligament  and  Fallopian  tubes.  Branches  are  given  off 
which  follow  the  round  ligament  through  the  inguinal  canal  to  the  integument 
of  the   labium   and  groin. 


PLATE  CCXLV 


°TERYG0ID  FOSSA 


,'fl\^         ~   TENSOR  PALATI 


^ INTERNAL  PTERYGOID 


SUPERIOR  CONSTRICTOR 


The  Pterygoid  Processes. 


LESSOX  CXLIV. 

Muscles  of  the  Thorax. 

External  intercostal*. — Description. — Then  are  eleven  of  these  on  each 
side,  extending  from  the  tubercles  of  the  ribs  posteriorly  to  the  commencement 
of  the  cartilages  of  the  ribs  anteriorly.  From  the  ant t  rior  <  xtremity  of  the  mus- 
cle the  anterior  intercostal  membrane  extends  forward  to  the  sternum.  The 
fibers  of  the  External  intercostals  pass  downward  and  forward  like  tin  fib 
the  External  oblique  muscle  of  the  abdomen.  A  firm  layer  of  fascia  covers  the 
outer  surface  of  the  External  intercostal  aswell  asthe  inn;  r  surface  of  tin  In- 
ternal intercostal  muscles.  The  middle  im<  rcostal  fascia,  which  is  more  deli- 
cate than  either  of  the  oth<  rs,  is  placed  b<  I \v<  <  n  the  two  set>  of  muscl<  s.  The 
Intercostal  fascia'  are  best  shown  In  twe<  n  the  External  intercostal  muscles  and 
rn  ui  n  anteriorly  and  b<  tw<  en  the  I  nit  rnal  int<  rcostals  and  the  spine  pos- 
teriorly, for  in  th<  m  situations  tin-  muscular  fiU  rs  arc  d<  fici<  at. 

Origin. — From  the  lower  border  of  each  rib  <  xtending  from  the  tubercles 
to  the  commencemi  nt  of  the  cartilag*  s. 

Insertion. — Into  the  upper  bord<  r  of  the  rib  below  extending  to  the  car- 
tilages in  the  two  lower  spaces,  but  in  tin   upper  two  or  three  not  quite  so  far. 

Action.— To  raise  the  ribs  so  as  to  increase  the  capacity  of  the  chest. 

Xki;\  e  Supply  .     Inn  rcostal  n<  rv<  s. 


458 


ANATOMY    IX    A    NUTSHELL. 


Blood  Supply. — Intercostal  arteries. 

Internal  intercostal*. — Description. — These  are  eleven  in  number.  Their 
tillers  pass  obliquely  downward  and  backward  in  the  opposite  direction  to  those 
of  the  External  intercostals.  They  extend  from  the  sternum  anteriorly  to  the 
angles  of  the   ribs   posteriorly. 

Origin. — From  the  inner  surface  of  each  rib  and  the  costal  cartilage. 

[NSERTION.      Into  the  upper  border  of  the  rib  below. 

Action. — To  depress  the  ribs  and  diminish  the  thoracic  cavity.  At  the 
from  of  the  chest  the  Internal  intercostal  muscles  help  the  External  intercostal 
muscles  in  raising  the  cartilages. 

PLATE  CCXLVI. 


MASTOID  PORTION 


MASSETER. 
CLASERIAN  FISSURE 
CLENOID    FOSSA. 

EXT.  AUDITORY   MEATUS 
STYLOID  PROCESS  - 
STYLO- GLOSSUS 
STYLO-HYOID 


^'.W^J^  TRACHELOMAST. 


DIGASTRIC. 
SPLEVHUS-CAPITIS. 
STERNOCLEIDOMASTOID- 
RETRAHENS  AURICULAM 

The  External  Surface  of  Temporal  Bone. 


PROCESS. 

STYLO- PHARYNGEUS. 


Nerve  Si  pply. — Intercostal  nerves. 

Blood  Supply.—  Intercostal  arteries. 

Infracostals,  also  called  Subcostals. — Description. — These  muscles  vary 
in  their  size  and  number  and  are  placed  on  the  inner  surface  of  the  ribs  where  the 
Internal  intercostals   cease. 

Origin. — From  the  inner  surface  of  the  rib. 

Insertion.  Into  the  inner  surfaci  >  of  the  first,  second  or  third  rib  below. 
Their  direction  is  like  thai  of  the  Internal  intercostals.  They  are  more  often 
presenl  between  the  lower  ribs  than  between  the  upper  ribs. 

Ai  i  [on.     Depress  ribs. 

N  u;\  i.  Si  I'i'i.i .     Intercostal  uerves. 

Blood  Supply.     Intercostal  arteries. 

Triangularis  sterni.  Des<  ription.-  This  muscle  is  situated  upon  the  inner 
wall  of  the  chesl  anteriorly  and  consists  of  thin  muscular  and  tendinous  fibers. 


ANATOMY    IN    A    NUTSHELL. 


459 


The  attachment  of  this  muscle  varies  not  only  in  different  bodies  but  on  the 
opposite  side  of  the  same  body.  The  superior  fibers  pass  vertically,  its  middle 
fibers  obliquely  outward,  and  its  lower  fibers  horizontally. 

Origin. — From  the  posterior  surface  of  the  ensiform  cartilage  and  the 
posterior  surfaces  of  the  sternal  end  of  the  costal  cartilages  of  the  three  or  four 
lower  true  ribs,  and  also  from  the  lower  one-third  of  the  posterior  surface  of 
the  sternum. 

Insertion. — Into  the  inner  surface  and  lower  border  of  the  costal  cartil- 
ages of  the  second,  third,  fourth,  and  fifth  ribs. 

Action. — Muscle  of  forced  expiration. 

Nerve  Supply. — Intercostal  nerves. 

Blood  Supply. — Intercostal  arteries. 

PLATE  CCXLVII. 


EMINENCE  FOR  SUP. 
SEMI-CIRCULAR  CANAL  \ 
SUP.  SURF. OF  PETROUS  PORTld 
FOR  SUP.  PETROSAL  SINUS 


SQUAMOUS 
PORTION. 


FOR  LATER  SINUS 

POST.  SURFACE  OF  PFTROUS  PORTION 


DEPRESSION  FOR 
CASSER1AN  GANGLION. 

CAROTID  CANAL 

'  OPENING  FOR  SMALLER  PETROSAL  N. 

HIATUS   FALLOPII 

INT  AUDITORY  MEATUS 

OPENINGFOR  PROC.OF  DURA-MATCR 

AQUEDUCTUS  VESTIBULI 


The  Petrous  Portion  of  the  Temporal  Bone. 

Levatores  costarum. — Description. — These  muscles  are  situated  between 
the  transverse  processes  of  the  seventh  cervical  vertebra  and  the  eleven  upper 
dorsal  vertebrae  and  the  border  of  the  first  rib  below  them.  There  are  twelve 
on  each  side  of  the  spine. 

Origin. — From  the  ends  of  the  transverse  processes  of  the  seventh  cervi- 
cal and  the  eleven  upper  dorsal  vertebra1.  Their  direction  is  obliquely  down- 
ward and  outward. 

Insertion. — Into  the  upper  bonier  of  the  firsl  rib  below  between  the 
tubercle  and  angle.  In  the  lower  Levatores  costarum  muscles  there  is  a  second 
insertion  to  the  second  rib  below  its  origin,  thus  where  this  is  true  each  rib  re- 
ceives fibers  from  the  transverse  processes  of  the  two  vertebras. 

Action. — Muscle  of  inspiration. 

Nerve  Supply. — Intercostal  nerves. 

Blood  Supply. — Intercostal  arteries. 


460 


ANATOMY    IN    A    NUTSHELL. 


LESSON  CXLV. 

The  mediastinum  is  the  -pace  in  the  thorax  which  contains  all  the  thoracic 
viscera  except  the  lungs.  This  word  comes  from  two  other  words — medius, 
the  mil  Idle,  ami  sto,  I  stand.  The  anterior  mediastinum  is  the  space  between 
the  sternum  anteriorly  and  the  pericardium  posteriorly.  It  contains  the  Tri- 
angularis sterni  muscle,  parts  of  other  muscles,  lymphatic  nodes,  and  areolar 
tissue.  The  middle  mediastinum  is  the  space  which  is  nearly  the  same  as  the 
pericardiac  cavity.  It  contains  the  heart,  the  ascending  aorta,  pulmonary 
artery,  and  the  superior  vena  cava, i.e.,  the  parts  of  these  which  are  within  the 
pericardium.  It  also  has  the  phrenic  nerves,  the  root  of  each  lung,  and  lym- 
phatic nodes.     The  posterior  mediastinum  is  the  space  between  the  spine  pos- 

PLATE  CCXLVIII. 


EUSTACHIAN   TUBE 
PROC.  COCHLEARIFORMIS. '  PROMONTORY.     STAPES 


CAROTID  CANAL/ 
CANAL  FOR    FENESTRA  ROTUNDA 
-[■<-•— q  TYMPANI.        PYRAMID. 
AQUEDUCTUS  FALLOPII 

ANTRUM 


^\         V  COCHLEARIFORMIS 
l^^EUSTACHIAN  TUBE 
C\\       TYMPANUM. 
CAROTID  CANAL. 


%&Y  ANTRUM.  \     STYL0I0  PROCESS. 

MARROW         AQUEDUCTUS  FALLOPII. 
CELLS. 


The  Temporal  Bone  Laid  Open. 

teriorly  and  the  pericardium  anteriorly.  It  contains  the  descending  aorta, 
the  azygos  v<  ins  the  thoracic  duct,  the  (esophagus,  pneumogastric  nerves,  and 
thi  splanchnic  aerves.  The  superior  mediastinum  is  the  space  which  has  in 
front  the  upper  pari  of  the  sternum  and  the  spine  behind.  It  is  situated  above 
the  pericardium  and  contains  all  the  forty  structures  which  pass  through  the 
superior  opening  in  the  thorax  except  the  apices  of  the  lungs  and  the  pleura'. 
For  structures  which  pass  through  the  superior  opening  in  the  thorax  see  page232. 
Name  and  classify  these  forty  structures. 


LESSON  CXLVI. 
Muscles  of  the  Superficial  Abdominal  Region. 
Obliquus  externus  also   called    Descending  oblique. — Description. — This 


ANATOMY    IN    A    NUTSHELL. 


461 


muscle  is  the  most  superficial  and  the  largesl  muscle  in  the  superficial  abdominal 
region.  It  is  situated  on  the  side  and  front  part  of  the  abdomen.  The  side  of 
the  muscle  consists  of  muscular  fibers  and  its  anterior  part  of  aponeurotic 
fibers.  The  aponeurosis  of  this  muscle  is  strong  but  thin,  and  its  fibers  pass 
obliquely  downward  and  inward.  At  the  linea  alba,  or  median  line  of  the  ab- 
domen, it  joins  the  aponeurosis  of  its  fellow.  It  is  connected  to  the  lower 
border  of  the  Pectoralis  major  above  and  below  its  attachment  extends  from 
the  anterior  superior  spine  of  the  ilium  to  the  spine  of  the  os  pubes  ami  theilio- 
pectineal  line,  thus  forming  Poupart's  ligament. 

Okigin. — From  the  external  surface  and  the  lower  borders  of  the  eight 
lower  ribs.  The  attachment  of  the  digitations  run  downward  and  backward. 
The  first  five  of  these  digitations,  which  increase  in  size  from  above  downward. 

PLATE  CCXLIX. 


CANAL  FOR  JACOBSON'S  NERVE 
AQUAIDUCTUS  COCHLEAR 
CANAL  FOR  ARNOLD'S  NERVE 
JUGULAR    FOSSA 
VAGINAL  PROCESS. 
STYLOID  PROCESS. 
STYLO-MASTOID  FOR  AM  E 
JUGULAR   SURFACE. 
OCCIPITAL  GROOVE.^ 
DIGASTRIC 
FOSSA. 


OPENING  OF  CAROTED  GANAL. 
QUAPLAT'L  ROUGH  SURFACE 
TENSOR   TYMPANI  MUSCLE 
LEVATOR  PALATI 
CANAL  FOR  EUSTACHIAN  TUBE 
AND,.TENSOR  TYMPANI  MUS. 

STYLO-PHARYNGEUS 
EMINENTIA 
ARTICULARIS 


The  Inferior  Surface  of  Petrous  Portion  of  Temporal  Bonf. 


are  received  between  the  corresponding  processes  of  the  Serratus  magnus  mus- 
cle, while  the  last  three  digitations  which  diminish  in  size  from  above  down- 
ward interdigitate  with  processes  of  the  Latissimus  dorsi  muscle. 

Insertion. — Into  the  anterior  half  of  th(  out<  r  lip  of  the  cr<  si  of  I  he  ilium, 
and  into  the  aponeurosis  of  the  muscle  extending  from  the  prominence  of  the 
ninth  costal  cartilage  to  the  anterior  superior  spinous  process  of  the  ilium. 

Action. — To  compress  the  viscera.  To  flex  the  thorax  on  the  pelvis  or 
to  flex  the  pelvis  on  the  thorax.  These  muscles  of  the  abdominal  wall  assisl 
in    micturition,   defecation,   and   parturition. 

Nerve  Supply.—  Lower  intercostals, 

BLOOD  SUPPLY.  —  Intercostal  and   lumbar  arteries. 

Obliquus  interims,  also  called  Ascending  oblique.  Description.  This 
muscle  lies  bfeneath  the  External  oblique  and  is  smaller  and  thinner  than  that 
muscle. 

Origin.-   From  the  outer  half  of  Poupart's  ligament,  from  the  anterior 


462  ANATOMY    IN  A    NUTSHELL. 

two-thirds  of  the  middle  lip  of  the  crest  of  the  ilium,  and  from  the  posterior 
layer  of  the  lumbar  fascia. 

Insertion. — Those  fibers  which  arise  from  Poupart's  ligament  arch  down- 
ward and  inward  over  the  spermatic  cord  in  the  male  and  the  round  ligament 
in  the  female,  and  arc  inserted  with  fibers  of  the  Transversalis  muscle  into  the 
cresl  of  the  os  pubes  and  the  pectineal  line  to  the  extent  of  half  an  inch.  The 
(•unjoined  tendon  is  formed  by  the  joining  of  the  Internal  oblique  muscle  and  the 
Transversalis  just  spoken  of.  The  part  of  the  muscle  which  arises  from  the 
anterior  one-third  of  the  middle  lip  of  the  crest  of  the  ilium,  passes  horizontally 
and  at  the  linea  semilunaris  it  divides  sending  the  lower  one-fourth  of  its 
aponeurosis  in  front  of  the  Rectus  muscle  to  be  inserted  into  the  linea  alba, 
while  the  upper  three-fourths  sends  a  layer  of  fascia  in  front  of  the  Rectus 
muscle  to  be  inserted  into  tbe  linea  alba  and  a  posterior  layer  to  pass  behind 
the  sheath  of  the  Rectus  muscle  to  be  inserted  into  the  linea  alba  also  into  the 
seventh, eighth. and  ninth  ribs.  That  part  of  the  muscle  which  passes  obliquely 
upward  is  inserted  in  the  lower  border  of  the  cartilages  of  the  three  lower  ribs 

PLATE  CCL. 

SUP.  BORDER 


^v 


MEDIAN         I' I' 
BORDER.     SI-,      .'/ 


LESSON  CXLVIL 

Transversalis.-  Description. — This  muscle  which  is  placed  beneath  the 
Internal  oblique  takes  its  name  from  the  direction  of  its  fibers. 

Oniiiix.  From  outer  one-third  of  Poupart's  ligament,  anterior  three- 
fourths  of  the  inner  lip  of  the  crest  of  the  ilium,  and  inner  surface  of  the  car- 
tilages of  the  lower  six  ribs,  interdigitating  with  the  Diaphragm.  It  also  comes 
from  the  lumbar  fascia. 

Insertion.— This  muscle  ends  in  a  broad  aponeurosis  the  lower  part  of 
which  joins  the   Internal  oblique  forming  the  conjoined  tendon.     The  remain- 


./  GROOVE  ^'^Bfc- 

■/  FOR  NASAL  NERVE.  \*.*$&s»^~ 

A? 

The  Nasal  Bone. 

where  it  is  continuous  with  the  Internal  intercostal  muscles.  The  outer  layer 
of  the  conjoined  tendon  is  called  the  ligament  of  Hesselback.  while  the  inner 
layer  is  called  the  ligament  of  Henle. 

A.CTION. — Same  as  External  oblique. 

Nerve  Supply.— Lower  intercostals.  ilio-hypogastric,  and  sometimes  the 
Uio-inguinal. 

Blood  Supply.  —  Intercostal  and  lumbar  arteries. 


ANATOMY    IX    A    NUTSHELL.  463 

iiig  part  of  the  aponeurosis  passes  horizontally  Towards  the  linea  alba,  but  at 
the  linea  semilunaris  it  passes  behind  the  Rectus  muscle  blending  with  the  pos- 
terior layer  of  the  Internal  oblique. 

Action. — Same  as  the  External  oblique. 

Nerve  Supply. — Intercostal,  ilio-hypogastric,  and  sometimes  the  ilio- 
inguinal. 

Blood  Supply. — Intercostal  and  lumbar  arteries. 

Rectus  abdominis. — Description. — This  muscle  extends  from  the  sym- 
physis pubes  to  the  sternum.  It  is  much  broader  and  thinner  above  than 
below  and  is  separated  from  its  fellow  by  the  linea  alba.  The  linea'  transversa 
are  tendinous  intersections  which  cross  this  muscle.  There  are  three  such 
lines.  One  is  situated  opposite  the  umbilicus  and  one  at  the  extremity  of  the 
ensiform  cartilage,  and  a  third  one  between  these  two.  Occasionally  one  or 
two  additional  lines  may  be  seen.  These  lines  are  homologues  of  ribs.  The 
sheath  of  the  Rectus  muscle  contains  the  Pyramidalis  muscle  and  the  superior 
epigastric  artery,  the  deep  epigastric  artery,  anel  the  terminal  branches  of  the 
lower  intercostal  and  lumbar  arteries  anel  nerves. 

PLATE  CCLI. 

LACHRYMAL 
GROOVE    \/wSjk 


HAMULUS 


The  Lachrymal  Bone. 

Origin. — By  two  heads.  (1)  the  external  or  Larger  head  being  attached  to 
the  crest  of  the  os  pubes.  (2)  the  internal  one  is  connected  with  the  ligaments 
covering  the  symphysis  and  interlacing  with  its  fellow  of  the  opposite  side. 

Insertion. — Into  the  cartilages  of  the  fifth,  sixth,  and  seventh  ribs,  and 
occasionally  connected  with  the  costo-ziphoid  ligaments  and  side  of  the  ensi- 
form cartilage. 

Action. — To  compress  abdominal  viscera,  and  to  flex  thorax. 

Xervk  Supply. — Lower  intercostals. 

Blood  Supply.  —  Intercostal,  lumbar,  deep  epigastric  and  superior  epigas- 
tric arteries. 

Pyramidalis. — Description. — This  muscle  is  situated  in  the  same  sheath 
with  the  Rectus  abdominis  muscle  in  front  of  the  lower  portion  of  that  muscle. 
It  may  be  absent  on  one  or  both  sides,  or  it  may  be  double  on  one  side. 

Origin. — From  front  of  pubic  bone  and  anterior  pubic  Ligament. 

Insertion. — Into  the  linea  alba  half  way  to  the  umbilicus. 

Action. — To  tense  linea  alba. 

Nerve  Supply. -Twelfth  thoracic  and  ilio-hypogastric. 


464 


ANATOMY    IN    A    NUTSHELL. 


Blood  Supply. — By  arteries  in  the  sheath  of  the  Rectus. 

Cremaster. — Description. — This  muscle,  which  consists  of  thin  musular 
fasciculi  which  are  continuous  with  those  of  the  Internal  oblique  and  some 
times  with  those  of  the  Trans versalis,  descends  through  the  external  abdominal 
ring  from  the  front  of  the  spermatic  cord. 

Origin. — From  the  middle  of  Poupart's  ligament. 

Insertion. — Into  the  crest  of  the  os  pubis  and  sheath  of  the  Rectus. 

Action. — To    retract    testicle. 

Nerve  Supply. — Genital  branch  of  the  genito-crural. 

Blood  Supply. — Spermatic  artery. 

PLATE  CCLII. 


FQRSUP.TURBINAL. 
RIDGE    FORMID.TURBINAL. 


ANTRUM 

POST.  PALATINE 
GROOVE. 

INF  MEATUS 

PALATINE  PROC. 


NASAL  PROC 


MIDDLE  MEATUS 


RIDGE  FOR 
NF.TURBINAL. 

ART  WITH  VOMER 

ANT.  NASAL 
SPINE. 

-CREST 

ANT  PALATINE 
£i      GROOVE. 


The  Internal  Surface  of  Superior  Maxillary  Bone. 

The  origin  and  insertion  of  this  muscle  is  similar  to  that  of  the  lower  fibers 
of  the  Internal  oblique.  This  muscle  is  found  in  the  male,  but  a  few  muscular 
fibers  may  be  seen  on  the  round  ligament  of  the  female  which  correspond  to 
this  muscle. 

LESSON  CXLVIII. 

Muscles  of  deep  Abdominal  Region. 

(1)  Psoas  parvus  which  has  been  described  on  page  134. 

(2)  Psoas  magnus  which  lias  been  described  on  page  134. 

(3)  Uiacus  which  has  been  described  on  page  135. 

(4)  Quadratus  lumboruni. — Description. — This  muscle  is  situated  in  a 
sheath  formed  l>v  the  anterior  and  middle  layers  of  the  lumbar  fascia.     On  the 


ANATOMY  IN  A  NUTSHELL.  465 

anterior  surface  of  this  muscle  beneath  this  fascia  are  the  last  dorsal,  ilio-hypo- 
gastric,  and  ilio-inguinal  nerves.  The  middle  layer  of  the  lumbar  fascia  sep- 
arates this  muscle  from  the  Erector  spinae.  This  muscle  as  its  name  implies 
is  quadrilateral,  broader  below  than  above. 

Origin. — From  the  ilio-lumbar  ligament  and  the  crest  of  the  ilium  for 
about  two  inches.  Occasionally  a  second  portion  of  this  muscle  is  found  situ- 
ated in  front  of  the  muscle,  and  when  so  found  it  has  its  origin  from  the  upper 
borders  of  the  transverse  processes  of  three  or  four  lower  lumbar  vertebrae  and 
is  inserted  into  the  lower  margin  of  the  last  rib. 

Insertion. — Into  the  apices  of  the  transverse  processes  of  the  four  upper 
lumbar  vertebrae  and  into  the  lower  border  of  the  last  rib  for  about  half  its 
length. 

Action. — To  draw  down  the  last  rib  and  acts  as  a  muscle  of  inspiration. 

Nerve  Supply. — Last  dorsal,  first  and  occasionally  the  second  lumbar. 

Blood  Supply. — Intercostal  and  lumbar  arteries. 


LESSON  CXLIX 

The  word  membrane  is  used  to  name  any  thin  expansion  of  tissue,  and  has 
the  following  classes:  (1)  Serous  membrane,  which  is  the  simplest  of  all 
forms.  These  serous  membranes  derive  their  name  from  the  fact  that  they 
are  moist  with  a  fluid  like  blood-serum.  The  serous  membranes  are  closed  sacs, 
such  as  the  pericardium,  pleura,  and  peritoneum.  However,  the  peritoneum 
in  the  female  is  an  open  sac.  (2)  Synovial  membrane  which  lines  the  joints. 
This  membrane  secrets  synovia,  which  resembles  the  white  of  egg.  Under 
synovial  membrane  we  have  three  classes,  (a)  articular,  which  occurs  hi  joints, 
(b)  vaginal,  which  is  found  where  the  tendons  of  muscles  run  over  bones,  (c) 
bursal.  A  synovial  bursa  is  a  bag  which  is  lined  with  synovial  membrane  and 
placed  between  the  tendon  of  a  muscle  and  a  bone,  or  two  muscles,  or  two 
tendons.  (3)  Mucous  membrane.  The  mucous  membrane  lines  open  cavi- 
ties.    (4)  Cutaneous  membrane,  which  is  commonly  called  skin. 

The  peritoneum  is  a  serous  membrane  with  a  smooth  shining  surface.  This 
membrane  is  transparent,  uncolored,  strong,  and  moist.  The  peritoneum  is 
reflected  from  the  abdominal  walls  and  from  pelvic  walls  over  the  viscera 
to  invest  and  at  the  same  time  hold  them  in  position.  The  part  which  lines  the 
abdominal  and  pelvic  wall  is  called  parietal  or  external  peritoneum,  and 
that  which  invests  the  viscera,  to  agreater  or  lessextent,  is  called  the  visceral 
or  internal  peritoneum.  If  it  were  possible  to  separate  the  entire  peritoneum 
from  the  body,  it  would  be  in  the  form  of  a  large  closed  sac  with  a  constric- 
tion a  little  above  its  center,  thus  forming  the  greater  and  lesser  sacs  of  the 
peritoneum.  The  passage  way  between  these  two  sacs  is  called  the  foramen 
OF  Winslow.  The  foramen  of  Winslowhas  above  it  the  caudate  lobe  of  the 
liver,  in  front  of  it  the  lesser  omentum,  below  it  the  duodenum,  and  hepatic 
vessels,  behind  it  the  inferior  vena  cava.  The  lesser  sac  of  the  peritoneum 
lies  back  of  and  below  the  stomach  and  liver,  while  the  greater  sac  lies  in  front 
and  below  these  viscera. 


466  ANATOMY  IN  A  NUTSHELL. 

The  peritoneum  (literal  meaning  is  stretched  around)  in  the  male  forms  a 
closed  sac.  Ln  the  female  it  tonus  an  open  sac  by  means  of  the  two  Fallopian 
tubes.  It  has  an  outer  or  parietal  layer  and  an  inner  or  visceral  layer.  It 
lines  mos1  of  the  viscera  of  the  abdominal  cavity  and  in  its  development  forms 
folds  and  ligaments.  The  lesser  sac  is  in  the  greater  omentum  but  the  greater 
sac  is  not  in  the  lesser  omentum.  A  fold  of  peritoneum  going  from  the  abdom- 
inal wall  to  the  small  intestine  is  called  the  mesentery.  A  fold  of  peritoneum 
going  from  the  lesser  curvature  of  the  stomach  to  the  transverse  fissure  of  the 
liver  is  called  the  lesser  omentum  and  a  fold  of  peritoneum  going  from  the  greater 
curvature  of  the  stomach  to  the  transverse  colon  is  called  the  greater  omentum. 

The  greater  omentum  has  four  layers  in  it  which  cannot  be  demonstrated 
in  the  adult  but  can  be  in  the  fetus.  The  lesser  omentum  has  two  folds  in  it.  A 
fold  of  peritoneum  passing  from  the  liver  to  the  spleen  is  called  gastro-splenie 
omentum.     All  other  folds  of  peritoneum  are  called  ligaments. 

The  following  eleven  structures  are  entirely  covered  with  peritoneum: 
(1)  Spleen,  (2)  liver.  (3)  stomach,  (4)  first  portion  of  the  duodenum,  (5) 
small  intestine,  (6)  csecum,  (7)  transverse  colon,  (8)  sigmoid  flexure,  (9)  first 
portion  of  the  rectum,  (10)  ovaries,  and  (11)  the  uterus. 

The  following  six  structures  are  entirely  stripped  of  peritoneum,  (1)  pan- 
creas, (2)  kidney.  (3)  suprarenal  capsule,  (4)  third  portion  of  the  rectum.  (5) 
anterior  portion  of  the  bladder,  and  (6)  lower  portion  of  the  vagina. 

Tracing  the  greater  sac,  (Plate  CLI.)  starting  at  the  umbilicus  and  de- 
scending, it  covers  the  anterior  abdominal  wall,  reflected  over  the  symphysis 
pubis,  over  the  posterior  portion  of  the  bladder,  overthe  uterus  and  the  anterior 
surface  of  the  rectum,  forming  a  pouch  called  the  pouch  of  Douglas,  up  the  pos- 
terior abdominal  wall  it  reaches  almost  to  the  pancreas  and  there  it  is  reflected 
towards  the  small  intestine  forming  the  posterior  layer  of  the  mesentery;  sur- 
rounding the  small  intestine  il  passes  up  to  the  abdominal  wall  again,  forming 
the  anterior  laverof  the  mesentery  and  thereit  is  reflected  over  to  the  transverse 
colon,  forming  the  posterior  layer  of  the  transverse  meso-colon;  from  there  ii 
forms  the  fourth  and  first  layers  of  the  greater  omentum,  passing  up  to  the  stomach 
ami  from  there  over  the  anterior  border  of  the  stomach  and  continuing  up  to 
the  transverse  fissure  of  the  liver  forming  the  anterior  layer  of  the  lesser  omentum. 
From  this  fissure  ii  continues  over  the  anterior  portion  of  the  liver,  forming 
the  suspensory  ligament  of  the  Liver,  from  there  being  reflected  on  the  anterior 
abdominal  wall  down   to  the  starting  point. 

The  lesser  sac  (Plate  CLI)  is  traced  from  the  posterior  surface  of 
the  liver,  descending  and  forming  the  posterior  layer  of  the  lesser  omentum. 
being  reflected  over  the  posterior  surface  of  the  stomach  and  from  there  form- 
ing the  second  and  third  Layersof  the  greater  omentum  and  from  there  ascend- 
ing and  forming  tli<'  anterior  laverof  the  transverse  meso-colon  up  to  the  pos- 
terior surface  of  the  liver. 

The  peritoneum  can  be  shown  as  a  closed  sac  best  by  a  transverse  section 
at  the  umbilicus!    (Plate  CL.) 

The  functions  of  the  peritoneum  are  as  follows:  (1)  It  secrets  serum  which 
Lubricates  its  adjacent  surfaces.  (2)   it  absorbs  any  excess  of  its  own  secretion 


rOMY  IX  A  XUT>HELL. 


4«  17 


M  well  as  foreign  material  which  may  be  introduce!  is  Ligatory  such  as 

the  falciform  ligament  of  the  liver.  (4)  it  is  pilieate.as  the  plica epigastrica  where 
it  makes  a  fold  over  the  episgastric  artery,  (5)  it  is  mi  which  hind  organs 

to  the  walls  of  the  abdomen  and  conducts  nutrient  nerves  and  vessels  to  the 
organs.  The  transverse  meso-colon  is  an  example  of  this.  (6)  It  is  omental. 
which  means  it  binds  one  organ  to  another.  An  example  the  gastro-splenic 
omentum.  An  omentum  may  or  may  not  contain  nutrient  nerves  and  vessels. 
Nerve  Slpply. — The  parietal  peritoneum  receives  its  nerve  supply  from 
the  sympathetic  through  the  gray  rami  commnnicantes.  The  visceral,  peri- 
toneum receives  its  nerve  supply  from  the  solar  plexus. 

PLATE  CCLIII. 


0     POST.  DENTAL  CANALS 
P-ARTIC.WITH  LACHRYMAL 
0- INFRAORBITAL  GROOVE. 
R  -MALAR  PROC. 
S  -ALVEOLAR   PROC. 


T-  INCISIVE  TOSSA. 
U-CANINE  FOSSA. 
V- CANINE  FMINENCE. 
W-OBRITAL  SURFACE. 
X- FACIAL  SUREACE. 
Y   ZYGOMATIC  SURFACE 
^A  Z-TUBEROSUY. 


A-0RB1CULAR1S- 

PALPEBRARUM 

B-TENDO-OCULI. 

C-LEV.LADU  SUP. 

AL/tQUE-NASI.  /:/* 
D-INF.OBUQUE. 

E-LEV.LABII- 
SUPERIORIS 

F  -  LEV.  ANG. 
ORIS. 

G-  COMPRESSOR 
MARIS. 

H-  DEPRESSOR 
ALAl-fJASl.     M 

I  -  MASSETER.  g 

J  -  BUCCIN- 
ATOR. 

K-  NASAL 
PROC 

L  -NASAL 
NOTCH. 

M-NASAL 

SPINE. 
N- NUTRIENT    FORAMINA. 

External  Surface  i  >f  Superk  »b  Maxill  \ky  B<  >ne. 

Blood  Supply. — The  parietal  peritoneum  receive-  its  blood  supply  from 
the  intercostals,  phrenic,  lumbar,  circumflex  iliac,  and  deep  epigastric  arteries. 
The  visceral  peritoneum  receives  its  blood  supply  from  the  gastric,  hepatic 

splenic,  renal,  ami  mesentery  arteries.      These  latter  arteries  nourish  organs. 


LESSON  CL. 

The  kidney  (Plate  CCLXVI)   belongs  to  the  urinary  system,  which  has 

but  one  function,  that  of  elimination,  while  the  alimentary  system  has  two 
functions,  appropriation  and  elimination.  The  kidney  is  bean-shaped  ami  is 
situated  between  the  spinous  processes  <<\  the  eleventh  dorsal  and  the  third 


468  ANATOMY  IN  A  NUTSHELL. 

lumbar.  The  right  kidney  is  a  little  lower  than  the  left  one  on  account  of  the 
liver  being  above  the  kidney  on  the  right  side.  The  scar,  or  the  point  where 
the  vessels  enter  and  leave  the  kidney  is  on  the  inner  border,  about  its  middle. 
Its  vessels  bear  this  relation  to  one  another,  the  renal  vein,  renal  artery,  and  the 
ureter,  from  before  backward.  The  kidney  is  entirely  stripped  of  peritoneum. 
It  has  above  and  in  front  of  it  the  suprarenal  capsule  which  has  something  to 
do  with  the  pigmentation  of  the  body  and  is  considered  by  some  as  belonging 
to  the  sympathetic  nervous  system.  The  kidney  has  the  following  dimensions, 
four  and  three-fourths  by  two  and  one-half  by  one  and  three-fourths  inches. 
It  weighs  from  four  to  six  ounces.  Its  nerve  supply  is  from  the  renal  plexus 
which  comes  from  the  solar  plexus.  Its  blood  supply  is  the  renal,  suprarenal, 
spermatic,  and  Lumbar.  The  right  renal  vein  contains  the  purest  blood  in  the 
body. 

The  outer  portion  of  the  kidney  is  called  cortex,  while  the  interior  is  called 
medullary  portion.  The  kidney  in  the  fetus  and  someof  the  lower  animals  looks 
like  a  bunch  of  grapes;  it  is  made  up  of  individual  lobes;  the  point  where  these 
lobes  coalesce  entirely  disappears  in  the  adult  kidney,  giving  the  appearance 
of  one  solid  body.  The  physiolological  kidney  consists  of  the  uriniferous  tubules. 
These  are  about  one-half  million  in  number  and  would  be  fifteen  miles  in  length 
if  placed  end  to  end.  This  uriniferous  tubule  consists  of  (1)  a  capsule  or  head, 
(2)  neck,  (3)  spiral  portion,  (4)  descending  portion,  (5)  loop,  (6)  ascending 
portion,  (7)  distal  spiral  portion,  (8)  convoluted  portion,  (9)  irregular  portion, 
(10)  arched  portion,  and  (11)  a  descending  portion.  (Plate  CCLXV.)  The 
capsule,  or  Malpighian  body,  takes  from  the  blood  the  water  and  lesser  salts, 
while  the  rest  of  the  tube  takes  the  more  important  salts  from  the  blood.  The 
medullary  portion  of  the  kidney  consists  of  Malpighian  pyramids,  eighteen  or 
twenty  In  number,  with  the  apex  towards  the  hilum  of  the  kidney.  The  apex 
consists  of  infundibula,  and  the  infundibula  make  the  calices,  the  calices  form 
the  pelvis  and  the  pelvis  opens  into  the  ureter.  Between  these  pyramids  is 
cortex,  the  same  as  the  cortex  of  the  outer  portion  of  the  kidney,  but  has  a 
special  name,  called  the  column  op  Bertin.  That  part  of  the  uriniferous 
tubules  consisting  of  a  straight  portion  and  the  two  spiral  portions  form  what 
is  called  the  medullary  ray,  or  the  pyramids  of  Ferrein,  the  base  of  the 
pyramid  is  on  the  base  of  the  Malpighian  pyramid  and  the  apex  is  towards  the 
periphery.  The  uriniferous  tubules  in  the  cortex  form  what  is  called  the 
labi  rinth. 

The  relations  of  the  right  kidney. 

Above. — Suprarenal  capsule. 

Ix  Front. — (1)  Suprarenal  capsule,  (2)  Liver,  (3)  Duodenum,  (4)  As- 
cending colon,  (5)  Jejuno-ileum. 

Bihim).  (1)  The  last  rib,  (2)  Diaphragm,  (3)  Quadratus  lumborum, 
(4)   Psoas  magnus.     (Plate  VIII.) 

The  relations  of  the  left  kidney. 

Above. — Suprarenal  capsule. 

In  Front. — (1)  Suprarenal  capsule,  (2)  Spleen,  (3)  Stomach,  (4)  Pan- 
creas, (5)  Splenic  flexure,  (6)  Descending  colon,   (7)  Jejuno-ileum. 


ANATOMY  IN  A  NUTSHELL.  469 

Behind. — (1)  The  last  rib,  (2)  Diaphragm,  (3)  Quadratus  Lumborum, 
(4)  Psoas  magnus.     (Plate  VIII.) 

The  organs  of  the  urinary  system  are,  (1)  the  two  kidneys,  which  form  the 
urine  from  the  materials  furnished  by  the  blood;  (2)  the  ureters,  which  con- 
vey the  urine  away  from  the  kidneys;  (3)  the  bladder  in  which  the  urine  is 
stored  until  it  is  discharged,  and  (4)  the  urethra,  a  tube  through  which  the 
urine  passes  from  the  bladder. 

The  kidney  is  a  glandular  structure  whose  function  is  the  purification  of 
the  blood  by  the  excretion  of  the  urine.  It  is  held  in  position  by  its  vessels, 
the  peritoneum  and  the  abundant  fatty  tissue.  This  fatty  tissue  forms  the 
"  adipose   capsule. ' ' 

The  hilum  of  the  kidney  is  the  place  on  the  median  side  of  the  kidney. 
corresponding  to  the  place  of  the  scar  on  the  bean.  It  is  where  the  ureter  goes 
out  and  the  vessels  and  nerves  enter.  The  capsule  of  the  kidney  is  a  smooth 
fibrous  membrane  closely  investing  the  kidney  and  forming  its  outer  coat. 

Floating  kidney  is  one  which  has  become  loose  and  displaced  hi  the  abdo- 
men. Surgical  kidney  is  a  term  somewhat  loosely  applied  to  nephritic  condi- 
tions, secondary  conditions  to  mischief  farther  down  in  the  urinary  tract,  but 
especially  to  suppurative  pyelonephritis  arising  from  cystitis. 

The  pelvis  or  sinus  of  the  kidney  is  the  concavity  or  re-entrance  at  the  hilum 
of  the  kidney.  The  calices  of  the  kidney  are  cup-like  or  infundibuliform  be- 
ginnings of  the  ureter  in  the  pelvis  of  the  kidney  surrounding  the  apices  of  the 
Malpighian  pyramids,  each  usually  receiving  more  than  one  pyramid.  There 
are  from  seven  to  thirteen  such  calices,  converging  and  uniting  in  the  infundi- 
bula,  which  in  turn  combine  to  form  the  pelvis.  The  infundibula  of  the  kidney 
are,  (a)  the  calices;  (b)  the  two  or  three  main  divisions  of  the  pelvis  of  the 
kidney  formed  by  the  confluence  of  the  calices. 

The  apices  of  the  Malpighian  pyramids,  also  called  mamillae,  are  the 
papillse  of  the  kidney.  The  Malpighian  pyramids  are  pale-reddish  conical 
masses  forming  the  medullary  part  of  the  kidney,  whose  apices  project  into  the 
calices  of  the  pelvis  of  the  kidney,  and  are  called  papillae.  The  Malpighian 
corpuscles  or  bodies  are  the  glomeruli  of  the  kidney  surrounded  by  its  capsule. 
These  form  the  terminations  of  the  branches  of  the  uriniferous  tubules,  occur 
in  the  cortical  substance  of  the  kidney,  and  are  about  in1,,,,  of  an  inch  in  dia- 
meter. They  are  formed  of  the  expanded  end  of  the  tube  invaginated  by  the 
bunch  of  blood  vessels  constituting  the  glomerulus  which  thus  are  embraced 
in  a  double  epithelial  sac,  and  the  blood  is  separated  from  the  lumen  of  the 
tubule  by  the  vascular  wall  and  the  epithelium  of  the  inner  layer  of  the  capsule. 

The  Malpighian  tuft  is  the  glomerulus  or  vascular  network  or  plexus  in  a 
Malpighian  body.  Marcello  Malpighi  (1628-94)  was  an  Italian  anatomisl  and 
physiologist. 

The  cortical  substance  of  the  kidney  is  the  outer  part  of  the  kidney  sub- 
stance which  contains  the  glomeruli.  The  columns  of  Bertin  are  named  after 
E.  F.  Bertin,  a  French  anatomist  (1712-81).  They  are  the  prolongations  in- 
ward of  the  cortical  substance  of  the  kidney  between  the  pyramids. 


470 


AX  ATOMY  IX  A   NUTSHELL. 


The  tubes  of  Ferrein  make  the  pyramids  of  Ferrein.  They  are  in  help  to 
the  cortical  substance  and  are  convoluted.  The  pyramids  ofFerrein  are  formed 
by  bundles  of  straight  and  convoluted  renal  tubules  which  constitute  the  medul- 
lary rays,  so  named  on  account  of  their  radiation  from  the  medulla. 

The  tubes  of  Bellini  are  the  excretory  tubes  opening  on  the  papilla.  They 
are  straight  tubes. 

The  tubes  of  Henle connect  those  of  Bellini  and  Ferrein.  They  are  looped 
tubes. 

The  capsule  of  Muller  is  the  dilated  extremity  of  a  tube  of  Ferrein  invest- 
ing the  Malpighian  tuft  probably  by  two  layers,  similar  to  the  pleural  invest- 
ment  of  the  lung's. 

PLATE  CCLIV. 


MASSETER 


Internal  Surface  of  the  Malar  Bone. 


The  nerve  SUPPLY  to  the  kidney  is  from  the  renal  plexus  which  is  formed 
by  filaments  from  the  solar  plexus  and  the  lesser  splanchnic  nerve. 

The  blood  supply  is  from  the  renal  artery  and  renal  vein,  (a)  Afferent 
(vessels  carrying  to),  (1>)  efferent  vessels  (carrying  from).  The  kidney  is  very 
vascular.  The  larger  arterial  branches  run  up  between  the  pyramids  of  Mal- 
pighi  to  subdivide  a1  their  bases  into  cortico-medullary  arches  which  lie  be- 
tween the  cortex  and  medulla,  giving  off  arterioles  in  both  directions,  the  cor- 
tical branches  supplying  afferent  twigs  to  the  glomeruli  within  the  capsules  of 
Bowman. 

The  medullary  branches  running  inwards  to  form  plexuses  around  the 
straight  and  looped  tubules  of  the  Malpighian  pyramids.  The  efferent  vessels 
of  the  Malpighian  glomeruli  form  a  capillary  plexus  around  the  uriniferous 
tubule-  and   terminate  in   renal   veins. 

The  surface  of  the  kidney  receives  small  arteries  which  pass  through  the 
fatty  capsule  from  the  suprarenal,  spermatic,  and  lumbar  vessels  .The  super- 
ficial veins  appear  in  the  form  of  little  stellate  groups  (stars  of  Yerhayen)  which 


ANATOMY  IN  A  NUTSHELL.  471 

communicate  with  the  venous  plexus  in  the  adipose  capsule  and  by  means  of 
this  with  the  visceral  and  parietal  veins  close  by.  These  vein>  are  very  dis- 
tinct when  the  organ  is  congested. 

The  renal  lymphatics  may  be  divided  into  two  sets,  capsular  and  parenchy- 
matous. They  terminate  in  a  series  of  glands  lying  with  the  renal  vessels  in 
the  subperitoneal  tissue,  and  their  contents  are  ultimately  conveyed  into  the 
receptaculum   chyli. 


LESSON  CLI. 

The  ureter  (Plate  VIII.)  is  a  tube  conveying  the  urine  from  the  kid- 
ney to  the  blader  in  mammals,  or  into  the  cloaca  in  case  no  bladder  exists. 
The  human  ureter  is  a  slender  tube  from  fifteen  to  eighteen  inches  long  running 
from  the  pelvis  of  the  kidney  to  the  base  of  the  bladder,  at  the  posterior  angle 
of  the  trigonum.     It  is  behind  the  peritoneum  and  rests  upon  the  Psoas  muscle. 

Its  structure  includes  (1)  a  fibrous  coat.  (2)  longitudinal  and  circular 
muscular  fibers,  and  (3)  a  lining  of  mucous  membrane  with  vessels  and  nerves 
from  various  sources.  The  ureter  pierces  the  wall  of  the  bladder  very  oblique- 
ly. It  runs  for  nearly  an  inch  behind  the  muscular  and  mucous  coats  of  the 
bladder. 

Blood  Supply. — (1)  The  renal,  (2)  Spermatic.  (3)  Internal  iliac,  and 
\     Inferior  vesical. 

Nerve  Supply. — (1)  Inferior  mesenteric.  (2)  Spermatic  plexus,  (3)  Pel- 
vic plexus. 

The  bladder  is  the  reservoir  in  which  the  urine  is  collected  from  the  ureters. 
It  has  four  coats.  (1)  the  mucous,  which  is  nearest  the  cavity.  (2)  the  areolar. 
(3)  the  muscular,  and  (-4)  the  serous.  The  trigonum  is  a  triangular  space  or 
area  at  the  base  of  the  bladder,  whose  apex  is  at  the  beginning  of  the  urethra. 
and  whose  other  two  angles  are  at  the  point  of  entrance  of  the  ureters  into  the 
bladder. 

When  the  bladder  is  collapsed  its  mucous  walls  fall  together  in  such  a  way 
that  a  sagittal  section  shows  the  line  between  them  in  the  shape  of  a  V  with 
unequal  and  widely  spread  arms,  the  point  of  the  V  indicating  the  opening  of 
the  urethra.  Its  dimensions  are  three  by  five  inches.  It>  capacity  is  about 
a  pint.  In  the  child  the  bladder  is  almost  an  abdominal  organ,  while  in  the 
adult  it  is  in  the  pelvis. 

The  urachus  is  a  fibrous  cord  extending  from  the  fundus  of  the  bladder  to 
the  umbilicus.  It  represents  in  the  adult  a  part  of  the  sac  of  the  allantoic  and 
associate  allantoic  vessels  of  the  fetus,  whose  cavities  have  been  obliterated. 
It  is  that  intra-abdominal  section  of  the  navel-string  which  is  constituted  by 
bo  much  of  the  allantoic  sac  and  hypogastric  arteries  a-  becomes  impervious, 
the  section  remaining  pervious  being  the  bladder  and  superior  vesical  arteries. 
It  sometimes  remains  pervious,  as  a  malformation,  when  the  child  may  urinate 
l)v  the  navel. 


472  ANATOMY    IN  A.    NUTSHELL. 

The  allantois  is  a  fetal  appendage  of  most  vertebrates,  developing  as  a  sac 
or  diverticulum  from  the  posterior  portion  of  the  intestinal  cavity.  It  is  one 
uf  the  organs  of  the  embryo  of  all  amniotic  vertebrates,  or  those  which  develop 
an  amnion,  but  is  wanting  or  is  most  rudimentary  in  amphibians  and  fishes, 
In  birds  and  reptiles  it  is  large  and  perforins  a  respiratory  function,  and  in 
mammals  contributes  to  form  the  umbilical  cord  and  placenta.  Its  exterior 
primitively  consists  of  mesoblast,  its  cavity  receiving  the  secretion  of  the  pri- 
mordial kidneys  (Wolffian  bodies).  So  much  of  the  sac  as  remains  pervious 
within  the  body  of  the  embryo  becomes  the  urinary  bladder,  or  in  some  degree 
a  urinary  passage. 

The  umbilical  arteries  and  veins  course  along  the  elongated  stalk  of  the 
sac,  which  becomes  the  umbilical  cord,  and  that  part  of  these  allantoic  vessels 
within  the  body  which  does  not  remain  pervious  become  the  urachus  and  round 
Ligament  of  the  liver. 

The  expanded  extremity  of  the  allantois,  in  most  mammals,  unites  with 
the  chorion  to  form  the  placenta.  In  those  vertebrates,  as  mammals,  in  which 
the  umbilical  vesicle  has  but  a  short  period  of  activity,  the  allantois  chiefly 
sustains  the  functions  whereby  the  fetus  is  nourished  by  the  blood  of  the  mother 
and  has  its  own  blood  arterialized.  In  parturition,  so  much  of  the  allantois 
as  is  outside  of  the  body  of  the  fetus  is  cast  off,  the  separation  taking  place  at 
the  navel. 

The  uvula  vesica?  is  a  slight  projection  of  mucous  membrane  from  the 
bladder  into  the  cystic  orifice  of  the  urethra. 

The  arteries  of  the  bladder  are  the  superior,  middle  and  inferior  vesical  and 
in  the  female  the  uterine  and  vaginal  also;  its  veins  are  radicles  of  the  internal 
iliac.  The  Lymphatics  accompany  the  veins  and  terminate  in  the  internal  iliac 
gland.  The  nerves  are  derived  partly  from  the  sympathetic  system  through 
the  hypogastric  plexuses,  partly  from  the  cerebro-spinal  system  through  the 
third  and  fourth  sacral  nerves.  The  former  supply  the  mucosa,  the  latter  of 
the  muscularis. 

The  bladder  is  held  in  place  by  ligaments  which  are  divided  into  true  and 
false.  The  true  ligaments  are  five  in  number;  the  two  anterior,  two  lateral, 
and  the  urachus  (superior).  Tin:  false  ligaments,  also  five  in  number,  are 
formed  by  folds  of  the  peritoneum.  The  false  are  named  the  two  posterior, 
two  Lateral  and  superior. 


LESSON  CLII, 

The  word  urethra  (Plates  CCLXXII-CCLXXIX)  is  derived  from  the  Greek 
which  means  to  urinate.  The  male  and  female  urethrae  differ.  It  is  a  modifica- 
tion of  a  pari  of  a  uro-genital  sinus  into  a  tube  ora  groove  for  the  discharge  of 
the  secretion  of  the  genital  <>r  urinary  organs  or  both;  in  most  mammals,  in- 
cluding man,  a  complete  tube  from  the  bladder  to  the  exterior,  conveying  urine 
and  semen  in  the  male  sex.  urine  only  in  the  female:  in  some  birds  a  penial 
groove  for  the  conveyance  of  semen  only.  The  urethra  in  the  male  is  always 
a  part  of  the  penis,  or  penial  urethra,  continuous  usually  with  the  urethral  part 


ANATOMY    IN    A    NUTSHELL. 


473 


of  the  urogenital  sinus;  that  of  the  female  is  only  exceptionally  a  part  of  the 
clitoris.  In  man  the  urethra  extends  from  the  bladder  to  the  end  of  the  penis, 
usually  a  distance  of  eight  or  nine  inches.  The  male  urethra  has  three  portions 
— the  prostatic,  the  membranous,  the  spongy — the  structures  and  the  rela- 
tions of  which  are  essentially  different.  Except  during  the  passage  of  the 
urine  or  semen  the  urethra  is  a  mere  transverse  cleft  or  slit  with  its  upper  and 
under  surfaces  in  contact.  At  the  orifice  of  the  urethra,  at  the  end  of  the  penis. 
the  slit  is  vertical  and  in  the  prostatic  portion  somewhat  arched.  The  pros- 
tatic portion  is  one  and  one-fourth  inches  long,  the  membranous  three-fourths 
of  an  inch  long,  and  the  spongy  four  and  one-half  inches  long.  The  first  and 
second  portions  are  not  subject  to  any  physiological  changes  such  as  character- 
ize the  third. 

PLATE  CCLV. 


FRONTAL  PROC. 


TEMPOROMALAR 
CANALS. 


LEVATOR 

l.ABU  SUP.    / 

ZYGOMATICS 'M1N- 


7YC0MATIC  PROC. 


ZYG0MAT1CUS  MAJ. 


External  Surface  of  Malar  Bone. 

The  urethra  has  three  coats,  mucous,  muscular,  and  erectile.  The  bulb 
of  the  urethra  is  the  posterior  enlarged  rounded  extremity  of  the  corpus  spong- 
iosum of  the  penis. 

The  crista  urethra  is  the  crest  of  the  urethra;  a  longitudinal  fold  of  mucous 
membrane  and  subadjacent  tissue  on  the  median  line  of  the  floor  of  the  pros- 
tatic urethra,  about  three-fourths  of  an  inch  in  length  and  one-fourth  of  an 
inch  in  height  where  it  is  greatest.  On  the  summit  open  the  ejaculatory  duct-. 
It  is  also  called  colliculus  seminalis,  caput  galliaginis,  and  veruinontanum. 

The  prostatic  sinus  is  a  longitudinal  groove  in  the  Hoor  of  the  urethra  on 
each  side  of  the  crest,  into  which  the  prostatic  ducts  open. 

The  pocularis  sinus  is  a  small  cul-de-sac,  from  a  quarter  to  hall'  an  inch  in 
its  greatest  diameter,  situated  at  the  middle  of  the  highest  part  of  the  crest 
of  the  urethra.  It  corresponds  with  the  uterus  of  the  female.  Also  called 
prostatic  vesicle,  utricle,  uterus  masculinus.  The  semilunar  ducts  open  on  the 
margins  of  the  sinus  pocularis. 

Cowper's  glands  (Plate  (VLXXIX)  are  a  pair  of  accessory  prostatic  or 
urethral  glands  of  lobulated  or  follicular  structure  which  pour  a  mucous  secre- 


474  ANATOMY    IN    A    NUTSHELL. 

tion  into  the  urethra  In  man  they  arc  small. about  the  size  of  a  pea,  Lying  be- 
neath the  membranous  portion  of  the  urethra,  close  behind  the  bulb  and  empty- 
ing into  the  bulbous  portion  of  the  tract.  Their  size,  shape,  and  position  vary 
in  different  animals,  in  some  of  which  they  are  much  more  highly  developed 
than    in    man. 

Tlie  tossa  navioularis  is  (a)  a  recess  in  the  urethra,  near  the  urinary  meatus, 
where  the  caliber  of  the  tube  is  enlarged.  (1»)  A  depressed  space  between  the 
posterior  commissure  of  the  vulva  and  the  fourchette. 

The  lacuna  magna  is  the  Largesl  of  several  orifices  of  mucous  follicles, 
situated  on  the  roof  of  the  fossa  naviculars. 

The  glands  of  Littre  are  the  crypts  along  the  spongy  portion  of  the  urethra. 

The  prostate  ("standing  in  front")  is  a  glandular  body  situated  around  the 
initial  portion  of  the  urethra.  It  develops  at  puberty,  atrophies  after  castra- 
tion, and  in  certain  animals  increases  in  size  during  the  breeding  season. 

The  female  urethra  is  a  tube  beginning  at  the  meatus  urinarius  Lnternus 
in  the  bladder  and  ends  at  the  meatus  urinarius  externus  in  the  vulva.  It  is 
about  one  ami  one-half  inches  long,  imbedded  in  the  anterior  all  of  the  vagina. 
perforating  the  triangular  ligament,  and  surrounded  by  the  fibers  of  the  Com- 
pressor urethrse  muscle.  Its  diameter  is  about  one-fourth  inch,  but  it  is  capable 
of  considerable  dilatation,  being  surrounded  by  softer  structures  than  those 
around  the  male  urethra.  When  dilated  far  beyond  its  usual  calibre  it  does 
not    lose  its   tone. 

LESSON   CLIII. 

The  literal  meaning  of  hernia  is  branch.  It  is  a  tumor  formed  by  the  dis- 
placement and  protrusion  of  a  part  which  has  escaped  from  its  natural  cavity 
by  some  aperture  and  projects  externally.  It  is  sometimes  called  rupture. 
We  may  have  hernia  of  the  brain  and  of  the  coverings  of  the  cord,  of  the  thorax. 
or  of  the  abdomen.  When  we  speak  of  hernia  without  any  qualification,  we 
mean  hernia  of  the  abdomen,  and  this  is  the  most  common  form,  consisting 
of  the  protrusion  of  some  part  of  the  viscera  through  a  natural  or  accidental 
aperture  in  the  inner  wall  of  the  abdomen,  the  external  skin  generally  remaining 
unbroken.     The  following  are  some  of  the  forms  of  hernia: 

1.  Cerebral  hernia,  which  is  a  protrusion  of  the  brain  through  an  open- 
ing in  tin'  cranial  walls. 

2.  Ci;i  RAL  HERNIA  or  FEMORAL  HERNIA   is  a  hernia  descending  beside  the 

femoral   vessels. 

'4.  Direct  inguin  \i.  hernia  is  a  hernia  of  the  intestine  or  omentum  which 
descends  through  the  inguinal  canal:  but  uo1  through  the  internal  abdominal 
ring  having  broken  into  the  canal  below  this  ring  in  Hesselbach's  triangle. 

4.  Tin:  [NDIRECT  or  OBLIQUE  [NGl  [NAL  HERNIA  is  a  hernia  whose  course 
is  thai  of  the  spermatic  cord  through  the  ingiunal  canal. 

5.  LUMBAR  HERNIA  is  a  hernia  in  the  loins  or  lumbar  region. 

6.  Phrenic  hernia  i-  a  hernia  projecting  through  the  Diaphragm  into 
one  of  the  pleural  cavities. 


ANATOMY  IN  A  NUTSHELL.  475 

7.  Strangulated  hernia  is  a  hernia  so  tightly  compressed  in  some  part 
of  the  channel  through  which  it  has  been  protruding  as  not  to  be  reducible  by 
ordinary  means,  as  by  the  application  of  pressure  and  tointerfere  with  the  cir- 
culation in  the  protruding  part. 

8.  Umbilical  hernia  is  a  henna  of  the  intestine  at  the  navel.  It  is  called 
exomphalos. 

The  following  are  the  principal  causes  of  hernia: 

1.  Tight  lacing,  because  it  diminishes  the  abdominal  cavity. 

2.  Crying  and  fretting,  bronchitis,  asthma,  cough. 

3.  Deposit  of  fat  in  the  omentum  because  it  increases  the  volume  and 
weight  of  the  parts  within. 

4.  Pregnancies  because  of  the  stretching  of  the  abdominal  walls. 

5.  Straining  in  defecation. 

6.  Phimosis  because  of  the  straining  to  expell  the  urine. 

7.  Feats  of  strength  as  in  lifting  heavy  weights. 

8.  Men  have  larger  inguinal  rings,  women  have  a  larger  femoral  arch,  so 
sex  has  something  to  do  with  the  kind  of  hernia. 

0.  Presence  of  the  spermatic  cor, I. 

10.  Deficiency  of  some  of  the  layers  below. 

11.  Persistence  of  the  original  process  of  the  peritoneum. 

12.  A  long  mesentery. 

The  inguinal  canal  is  parallel  to  Poupait's  ligament  and  just  aboveit,  ex- 
tending from  the  internal  abdominal  ring  to  the  external  abdominal  ring.  It 
is  about  an  inch  and  a  half  long.  This  is  a  potential  canal,  but  for  a  short  time 
in  the  later  months  of  fetal  life  it  is  a  real  canal.  The  spermatic  cord  in  the 
male  and  the  round  ligament  in  the  female  pass  through  this  canal.  Its 
direction  is  downward,  forward  and  inward. 

The  relations  of  the  inguinal  canal. 

In  Front. — (1)  Skin.  (2)  Superficial  fascia.  (3)  External  oblique  muscle 
for  all  the  way,  (4)    Internal  oblique  muscle  for  the  outer  third  of  the  canal. 

Below. — The  union  of  the  transversalis  fascia  with  Poupart's  ligament. 

Behind. — (1)  The  conjoined  tendon.  (2)  Transversalis  fascia,  (3)  Triangu- 
lar fascia,  (4)   Subperitoneal  tissue.  (5)    Peritoneum. 

Above. — Arched  fibers  of  the  Internal  oblique  and  Transversalis  muscles. 

The  COVERINGS  OF  THE  [NDIRECT  nii  oblique  inguinal  hernia  from 
within  outward  ark: 

1.  Peritoneum,  which  is  the  proper  hernial  sac. 

2.  Extra-peritoneal  fat.     This  is  almost   inappreciable. 

3.  Infundibuliform  fascia,  which  Ls  from  the  internal  abdominal  ring. 

4.  Crematseric  fascia,  which  is  from  the  inguinal  canal. 

5.  Intercolumnar  fascia,  which  is  from  the  external  abdominal  ring. 

6.  Two  layers  of  superficial  fasica. 

7.  Skin. 

The  coverings  of  the  direct  [ngi  enal  hernia  from  within  outward 
are: 


476 


ANATOMY    IN    A    NUTSHELL. 


1.  Peritoneum. 

2.  Extra-peritoneal  fat. 
.'■>.  Transversalis  fascia. 

4.  Conjoined  tendon,  which  takes  the  place  of  cremasteric  fascia  in  the- 
indirect  hernia. 

5.  Intercolumnar  fascia,   which  takes  the  place  of  infnndibnliform  in  the 
indirect  hernia. 

6.  Two  layers  of  superficial  fascia. 

7.  Skin. 

PLATE  CCLVI. 


CORONOID 
PROC. 


A-MASSETER. 

B-BUCCINATOR. 

C-LEVATOR-MENTI. 

D-DEPRESSOR-LABU-  INF. 

E-DEPRESSOR-ANGULI-ORIS 

F-PLATYSMA-MYOIDES. 

G- MENTAL  FORAMEN. 


MENTAL    m/A  ' 


PROC. 


groove  for  facial  artery. 
External  Surface  of  Inferior  Maxillary  Bone. 


The  external  abdominal  ring  (Plate  XV)  is  a  potential  opening  in  the  apon- 
eurosis of  the  External  oblique  muscle  which  is  made  by  the  divergence  of  two 
of  its  fasciculi.  The  size  of  this  opening  varies  on  account  of  the  strength  of 
its  sides  or  pillars.  It  is  about  an  inch  long  and  half  an  inch  wide.  It  is  situ- 
ated above  and  to  the  outer  side  of  the  crest  of  the  os  pubis.  The  spermatic 
cord  in  the  male  and  the  round  ligament  in  the  female  passes  through  this 
opening  to  pass  from  the  abdomen. 

The  relations  of  the  external  abdominal  ring. 

Above. — A  series  of  curved  fibers  called  the  intercolumnar. 

Below. — The  crest  of  the  os  pubis. 

On  Either  Side. — Columns  or  pillars  of  the  ring. 


ANATOMY  IN  A  NUTSHELL.  477 

The  internal  abdominal  ring  (Plate  XV)  is  situated  about  half  way  between 
the  anterior  superior  spine  of  the  ilium  and  the  symphysis  pubis.  It  Is  about 
half  an  inch  above  Poupart's  ligament  and  in  the  transversalis  fascia.  This 
is  also  a  potential  opening.     This  is  much  larger  in  the  male  than  in  the  female. 

The  relations  of  the  internal  abdominal  ring. 

Above  and  Externally. — Arched  fibers  of  the  Transversalis  muscle. 

Below  and  Internally. — Deep  epigastric  vessels. 

The  spermatic  cord  in  the  male  and  the  round  ligament  in  the  female  pass 
through  this  opening. 

Gimbernat's  ligament  is  about  a  half  an  inch  in  length  and  larger  in  the 
male  than  in  the  female.  In  the  erect  posture  it  is  almost  horizontal  in  direc- 
tion with  its  base  directed  outward,  it  being  triangular  in  form.  It  is  derived 
from  the  External  oblique  muscle  and  is  reflected  downward  and  outward  from 
the  spine  of  the  os  pubis  to  be  inseretd  into  the  pectineal  line.  Its  anterior 
margin  is  continuous  with  Poupart's  ligament. 

The  triangular  ligament  of  the  abdomen  is  attached  by  its  apex  to  the 
pectineal  line  where  it  is  continuous  with  Gimbernat's  ligament.  From  there 
it  passes  inward  beneath  the  spermatic  cord  behind  the  inner  pillar  of  the  ex- 
ternal abdominal  ring  and  in  front  of  the  conjoined  tendon  to  the  linea  alba 
where  it  joins  its  fellow. 

Poupart's  ligament  is  formed  by  the  fascia  of  the  External  oblique  muscle 
of  the  abdomen  and  passes  from  the  anterior  superior  spine  of  the  ilium  to  the 
spine  of  the  os  pubis.  This  ligament  lies  beneath  the  spermatic  cord  and  is 
called   crural   arch. 


LESSON  CLIV. 

Femoral  hernia  passes  below  Poupart's  ligament  and  passes  down  towards 
the  saphenous  opening  in  the  femoral  or  crural  canal.  If  it  passes  through  this 
opening  it  is  called  complete,  if  it  does  not  it  is  called  incomplete. 

The  coverings  of  a  femoral  hernia  from  within  outward  are: 

1.  Peritoneum. 

2.  Subserous  areolar  tissue,  called  the  fascia  propria  of  Cooper. 

3.  Septum  crurale,  which  is  from  the  femoral  ring. 

4.  Crural  sheath,  which  is  from  the  transversalis  fascia. 

5.  Cribriform  fascia,  which  is  from  the  saphenous  opening. 

6.  Superficial  fascia.      Its  superficial  layer. 

7.  Skin. 

The  femoral  sheath  is  funnel-shaped  and  has  three  compartments  in  it. 
The  outer  one  is  for  the  femoral  artery.  THE  MIDDLE  ONE  tor  the  femora]  vein, 
and  the  internal  one  for  the  femoral  canal.     (Plate  XVI). 

The  femoral  canal  is  about  three-fourths  of  an  inch  Long  and  extends  from 
the  femoral  ring  above  to  the  saphenous  opening  below. 

The  relations  of  the  femoral  canal. 

In  Front. — Transversalis  fascia. 


178  ANATOMY    IN   A   NUTSHELL. 

Behind. — Iliac  fascia. 

Kvn  i;\  \i.ly. — A  septum  between  it  and  the  vein. 

Internally. — Gimbemat's  ligament  and  the  meeting  of  the  iliac  fascia 
and  the  transversalis  fascia. 

The  femoral  ring  is  the  upper  opening  of  the  femoral  canal  and  is  oval 
shaped  about  half  an  inch  in  diameter.     It  is  larger  in  women. 

The  relations  of  the  femoral  ring. 

I.\  Front. — Poupart's  ligament  and  the  deep  crural  arch  which  is  a  thick- 
ening of  the  transversalis  fascia. 

Behind.     The  Pectineus  muscle  and  the  ilio-peetin'eal  line. 

[ntern  u.i.y. — Gimbernal  's  ligament. 

Extern  u.i.v.-    Femoral  vein. 

It  is  closed  by  the  septum  crurale.  which  is  composed  of  fatty  connective 
tissue  and  is  perforated  by  lymphatics  passing  from  the  superficial  to  the  deep 
group.  There  is  a  small  lymphatic  gland  here.  On  the  upper  and  outer  angle 
of  this  ring  is  the  deep  epigastric  artery.  On  the  upper  and  inner  margin  is 
the  obturator  artery,  when  it  arises  from  a  common  trunk  with  the  deep  epi- 
gastric artery  which  it  does  in  about  thirty  per  cent  of  the  cases. 

The  coverings  of  the  umbilical  hernia  are: 

1.  Peritoneum. 

2.  Extra-peritoneal  fatty   tissue. 

3.  Transversalis  fascia. 

4.  Prolongation  of  scar  tissue  of  the  umbilicus  stretched  out. 

0.  Superficial  fascia. 
(i.  Skin. 

Congenital  hernia  (Plate  CCLXXXVIII)  is  applied  to  hernia  which  takes 
place  from  birth  or  during  any  period  of  life,  if  the  conditions  favorable  to  its 
occurrence  existed  at  birth.  The  vaginal  portion  of  the  tunica  vaginalis  may 
not  close  after  the  descenl  of  the  testicle  in  the  fetus,  and  in  this  case  when  there 
is  a  hernia  the  intestine  does  not  push  forward  a  sac  which  comes  from  the 
parietal  layer  of  the  peritoneum,  but  instead  it  lies  in  a  sac  formed  by  the 
tunica  vaginalis  which  is  still  connected  with  the  peritoneal  cavity.  These 
forms  of  hernia  ate  called  congenital  and  are  always  oblique. 

The  following  are  the  different  kinds  of  congenital  hernia: 

1.  Hernia  in  the  tunica  \  vginalis  testis.  In  this  form  of  congenital 
hernia  the  intestine  surrounds  the  testis  and  the  sac  is  formed  by  the  tunica 
vaginalis  testis,  because  the  intestine  passes  through  the  narrow  canal  which 
is  present  between  the  cavity  of  the  peritoneum  and  the  tunica  vaginalis  tes- 
tis, the  original  communication  between  them  is  not  obliterated. 

2.  Hernia  in  the  funIcular  portion  of  the  tunica  vaginalis.  In 
this  form  of  congenital  henna  the  sac  is  formed  by  the  original  pouch  of  the 
peritoneum  which  descends  with  the  testicle  but  is  shut  off  from  the  tunica 
vaginalis  testis  by  a  thin  septum.  The  canal  above  this  septum  being  still 
presenl  and  communicating  with  the  peritoneal  cavity. 

'.].  Infantile  hernia.  This  form  of  congenital  hernia  is  rare  and  is  pro- 
duced by  the  descent   of  the  hernia  through  the  internal  abdominal  ring  but 


ANATOMY    IN    A    NUTSHELL. 


479 


behind  this  abnormal  extension  of  the  tunica  vaginalis,  in  this  case  there  arc 
three  layers  of  peritoneum  in  front  of  the  hernia,  two  of  them  arc  from  the 
tunica  vaginalis  and  the  third  from  the  sac  around  the  hernia.  In  this  form  of 
hernia  the  tunica  vaginalis  testis  may  pass  up  as  high  as  the  internal  abdominal 
ring. 

4.  Encysted  hernia.  This  is  the  rarest  of  all  forms  of  congenital  hernia 
and  is  formed  by  the  hernia  pushing  the  closing  septum  of  the  internal  abdom- 
inal ring  as  a  diverticulum  into  the  unclosed  tunica  vaginalis. 

PLATE  CCLVII. 


MUSCLES 
A-EXT.  PTERYGOID 
B-INT.  PTERYGOID 
C-TEMPORAL. 
D-BUCCINATOR 


GROOVES  LIG'MTS.LTr. 

J-MANDIBULAR  SPINE. 

K- MANDIBULAR  FORAMEN 

L-SPHENO-MAND'R  LIG'MT. 

M-STYLO-MAND'R  LIG'WT 
E-SUP.  CONSTRICTOR.  N-GROOVE  FOR  SUBMAY'Y  GLAND. 
F-MYLO-HYOID.  O-GR00VE  FOR  SUBLING'L  GLAND 

G-GENI0-HYO-GL0SSUS.P-MYLO-HYOID  GROOVE 
H-GENIO-HYOIDEUS.       3-MYLO-HYOID  RIDGE. 

R-CAPSULE. 


Internal  Surface  of  Inferior  Maxillary  Bone. 


LESSON  CLV. 


Veins. 

Every  vessel  that  Leaves  the  heart  is  called  an  artery,  and  every  vessel  thai 
enters  the  heart  is  called  a  vein.  Arteries,  as  a  rule,  carry  pure  blood,  while 
the  veins  carry  impure  blood  bu1  there  are  exceptions  to  each  of  these  cases. 
The  pulmonary  arteries  carry  impure  blood  while  the  pulmonary  veins  carry 
pure  blood.  As  a  general  thing  veins  have  valves  and  arteries  do  not  have 
valves,  but  there  arc  exceptions  to  tins  rule,  for  the  pulmonary  artery  has  a 
valve  and  the  pulmonary  veins  do  not  have  valves.  Veins,  like  arteries,  have 
three  coats,  and  the  middle  coai  like  that  of  the  artery  lias  sympathetic  fibers 
around  it  but  not  so  well  developed  as  in  the  arteries. 


480  ANATOMY    IN    A    NUTSHELL. 

The  veins  of  the  dura  mater  of  the  brain  are  called  sinuses,  also  cavities  in 
bones  arc  called  sinuses.  After  the  blood  has  left  the  heart  by  way  of  the 
arteries  and  nourished  the  entire  body,  it  comes  back  to  the  heart  by  means  of 
veins.  We  have  a  pulmonary  venous  system  and  a  systemic  venous  system. 
The  veins  of  the  upper  extremity  have  been  described  on  page  117  and  the  veins 
of  the  lower  extremity  have  been  described  on  page  192.  We  will  now  give  the 
remaining  veins  of  the  body. 

Tin:  Veins  ok  the  Exterioe  of  the  Head  and  Face. 

1.  The  frontal  vein  passes  down  the  middle  of  the  frontal  bone  to  the  inner 
canthus  of  the  eye,  after  which  it  is  called  angular.  It  lies  parallel  with  its 
fellow  of  the  opposite  side  which  it  joins  by  a  transverse  branch  just  before  it 
reaches  the  root  of  the  nose.  At  their  beginning  the  frontal  veins  communi- 
cate with  the  temporal  veins.  At  the  inner  angle  of  the  orbit  they  receive  the 
the  supraorbital  veins.      Plate  CXV. 

2.  The  supraorbital  vein  lies  on  the  forehead  externally  to  the  frontal  vein 
which  it  joins  to  form  the  angular  vein  at  the  inner  angle  of  the  orbit. 

3.  The  angular  vein  passes  from  the  inner  canthus  of  the  eye  where  it  is 
formed  by  the  two  veins  just  mentioned  and  passes  to  the  base  of  the  nose.  Its 
radicles  are  (a)    supraorbital,  (b)  frontal,  (c)  superior  palpebral,  and  (d)  nasal, 

4.  From  the  base  of  the  nose  this  vein  continues  as  the  facial,  which  passes 
under  the  Zygomatici  muscles  and  over  the  anterior  border  of  the  Masseter 
muscle  in  a  groove  on  the  inferior  maxillary  bone.  From  here  it  passes  into 
the  internal  jugular  after  communicating  with  the  external  jugular.  Its  radi- 
cles are  (a)  angular,  (b)  inferior  palpebral,  (c)  dorsal  and  lateral  nasal,  (d) 
anterior  internal  maxillary  (deep  facial),  (e)  coronary  (superior  and  inferior), 
(f)  buccal,  (g)  masseteric,  (h)  labial,  (i)  submental,  (j)  ascending  palatine,  (k) 
tonsillar,  (1)  glandular  (parotid  and  submaxillary),  (m)  part  of  the  temporo- 
maxillary. 

5.  Temporal  vein  is  formed. by  the  anterior  temporal  and  posterior  tem- 
poral which  collects  the  blood  from  the  side  and  the  vertex  of  the  head  and 
after  uniting  above  the  zygoma,  passesover  the  zygoma  to  be  situated  in  front 
of  the  ear  between  the  condyle  of  the  jaw  and  the  external  auditory  meatus. 
It  now  passes  in tn  the  substance  of  the  parotid  gland  where  it  receives  the  in- 
ternal maxillary  vein  to  form  the  temporo-maxillary  vein.  The  radicles  of 
this  vein  are  (a)  anterior  temporal,  (b)  posterior  temporal,  (c)  middle  temporal, 
(d)  parotid,  (e)  anterior  auricular,  (f)  transverse  facial. 

6.  The  internal  maxillary  vein  is  formed  by  radicles  which  correspond  to 
the  branches  of  the  internal  maxillary  artery.  These  radicles  form  the 
pterygoid  plexus  of  veins,  and  this  plexus  of  veins  communicates  with  the  facial 
vein  by  the  anterior  internal  maxillary  vein  or  deep  facial. 

7.  The  temporo-maxillary  vein  is  formed  by  the  temporal  and  internal 
maxillary  veins  in  the  substance  of  the  parotid  gland.  At  the  angle  of  the  jaw 
it  joins  the  posterior  auricular  to  form  the  external  jugular.  It  may  however, 
divide  into  an  anterior  branch  which  joins  the  facial  vein  and  a  posterior  branch 
which  joins  the  posterior  auricular  to  form  the  external  jugular. 


ANATOMY    IN    A    NUTSHELL.  4S1 

S.  The  posterior  auricular  vein  conies  from  a  plexus  on  the  side  of  the  head 
and  hack  of  ear.  It  receives  the  stylo-mastoid  vein  and  branches  from  the 
external  ear.      It  joins  the  temporo-maxillary  to  form  the  external  jugular. 

9.  The  occipital  vein  is  formed  from  a  plexus  at  the  hack  part  of  the  vertex 

of  the  skull.  It  is  placed  deeply  between  muscles  of  neck.  It  passes  over  the 
suboccipital  triangle  under  theComplexus  muscle  where  it  communicates  with 
the  vertebral  vein.  It  empties  into  the  internal  jugular  as  a  rule,  hut  occasion- 
ally into  the  external  jugular. 

The  Veins  of  the  Neck.     (Plate  CXV.) 

1.  The  external  jugular  vein  collects  the  blood  from  the  exterior  part  of 
the  cranium  and  the  deep  part  of  the  face.  It  is  formed  by  the  junction  of  pari 
of  the  temporo-maxillary  trunk  and  the  posterior  auricular  veins  in  the  sub- 
stance of  the  parotid  gland  at  the  angle  of  the  jaw.  From  this  point  it  passes 
down  beneath  the  Platysma  myoides  muscle  over  the  Sterno-cleido-mastoid 
muscle  and  ends  near  the  clavicle  in  the  subclavian  vein.  Sometimes  it  empties 
into  the  internal  jugular  vein.  It  has  two  pairs  of  valves  which  do  not  prevent 
the  regurgitation  of  blood,  as  they  are  not  complete  valves.  The  portion  of 
the  vein  between  the  two  valves  is  called  a  sinus.  The  upper  pair  of  valves  is 
about  an  inch  and  a  half  above  the  clavicle,  while  the  lower  pair  is  at  its  temi- 
nation  into  the  subclavian  vein.  Its  radicles  are  (a)  posterior  external  jugular, 
(b)  suprascapular,  (c)  transverse  cervical,  (d)    frequently  the  anterior    jugular. 

2.  The  posterior  external  jugular  vein  receives  the  blood  from  the  integu- 
ment and  muscles  in  the  tipper  and  back  part  of  the  neck  and  also  from  the 
occipital  region.  It  lies  between  the  Splenitis  and  Trapezius  muscles.  It 
empties  into  the  middle  of  the  external  jugular  vein. 

'A.  The  anterior  jugular  vein  aiises  near  the  hyoid  bone  and  is  formed  by 
the  superficial  veins  of  the  submaxillary  region.  It  collects  the  blood  from  the 
superficial  muscles  and  integument  of  anterior  and  middle  regions  of  neck.  It 
joins  its  fellow  just  above  the  sternum.  Ii  empties  into  the  subclavian  or  ex- 
ternal jugular  vein.     It   has  no  valves. 

4.  The  internal  jugular  vein  collects  the  blood  from  the  brain  and  the 
superficial  pint  of  the  face.  It  is  formed  by  the  inferior  petrosal  sinus  and 
lateral  sinus.  It  passes  down  the  side  of  the  neck  in  the  common  carotid  sheath 
on  the  outer  side  of  the  carotid  artery.  For  contents  of  this  sheath  see  page 
282.  It  joins  the  subclavian  vein  near  the  inner  margin  of  the  Scalenus  ami- 
cus muscle.  It  is  provided  with  a  pair  of  valves  which  are  placed  about  three- 
fourths  of  an  inch  above  its  termination.  Its  radicles  are  (a)  pharyngeal, 
d>)  lingual,  and  under  lingual  we  have  dorsal  of  tongue  and  Lingual  vena  comites 
and  ranine,  (c)  common  facial,  (d)  superior  thyroid,  under  which  we  have  laryn- 
geal and  ci'ico-t hyroid,  (e)  middle  thyroid,  (f)  occipital,  which  may  be  a  radicle 
of  the  external  jugular. 

.").  The  vertebral  vein  commences  in  the  occipital  region  and  drains  the 
deep  muscles  at   the  upper  and  back  pari  of  the  neck.      This  is  more  of  :i  plexus 

of  veins  than  one  large  vein  and  they  run  down  through  the  foramina  in  the 


482 


ANATOMY    IN    A    NUTSHELL 


transverse  processes  of  the  cervical  vertebra?.  When  they  reach  the  sixth  cer- 
vical vertebra  they  form  two  main  trunks,  one  of  which  passes  through  the 
foramen  in  the  transverse  process  of  the  sixth  cervical  vertebra  and  the  other 
through  thai  of  the  seventh.  They  now  unite  into  a  common  trunk  which 
empties  into  the  back  pari  of  the  innominate  vein.  One  pair  of  valves  guard 
its  mouth.  The  radicles  of  the  vertebral  vein  are  (a)  muscular,  (b)  dorsi-spinal, 
(c)  meningo-rachidian,  (d)  ascending  cervical,  (e)  deep  cervical, (f)  first  inter- 
costal. 

The  deep  cervical,  also  called  posterior  vertebral,  lies  between  the  Com- 
plcxus  and  the  Semispinalis  muscles.  It  accompanies  the  profunda  cervicis 
aitery.      It  empties  into  the  lower  end  of  the  vertebral  vein. 

PLATE  CCLVIII. 


INFUNDIBULUM 


ETHMOIDAL      CANALS 


MIDDLE       TURBINATED 

uncinate    process 
Lateral  View  of  the  Ethmoid. 


LESSON  CLVI. 

The  axillary  vein  commences  at  the  lower  border  of  the  axillary  space  and 
receives  radicles  corresponding  to  the  branches  of  the  axillary  artery.  At  the 
outer  border  of  the  first  rib  it  continues  as  the  subclavian  vein.  Below  the 
Lower  border  of  the  tendons  of  the  Teres  major  and  Latissimus  dorsi  it  is  called 
basilic  It  has  a  pair  of  valves  opposite  the  lower  border  of  the  Subscapularis 
muscle.  At  the  termination  of  the  cephalic  vein  and  the  subscapularis  vein. 
valves  arc  also  found. 

The  subclavian  vein  is  a  continuation  of  the  axillary  vein  at  the  outer 
border  of  the  first  rib  to  the  inner  end  of  the  clavicle  where  it  joins  the  internal 
jugular  vein  and  makes  the  innominate  vein.  The  external  jugular  vein  empties 
into  this  veil]  and  the  anterior  jugular  may  empty  into  it.  The  Scalenus  anti- 
cus  muscle  and  the  phrenic  nerve  separate  this  vein  from  the  subclavian  artery. 
It  has  valves  about  an  inch  from  its  termination. 

The  right  innominate  vein,  which  is  about  an  inch  long,  is  formed  behind 
the  inner  end  of  the  clavicle  by  the  internal  jugular  and  subclavian  veins.     It 


ANATOMY    IN    A    NUTSHELL.  483 

passes  downward  to  join  the  left  innominate  vein  at  the  inferior  border  of  the 
first  right  costal  cartilage  to  make  the  superior  vena  cava.  Its  radicles  are. 
(a)  right  vertebral,  (b)  right  internal  mammary,  which  are  two  for  each  artery 
but  uniting  into  a  common  trunk  before  entering  into  the  innominate  vein, 
(c)  right  inferior  thyroid,  which  are  three  or  four  in  number  pass  from  the  thy- 
roid venous  plexus  into  the  left  innominate  vein,  (d)  right  superior  intercostal, 
receives  the  blood  from  the  second  and  third  intercostal  spaces. 
The  right  lymphatic  duct  opens  at  the  angle  where  the  right  subclavian  vein 
joins  the  right  internal  jugular  vein. 

The  left  innominate  vein,  which  is  about  three  inches  long,  is  larger  than 
the  right.  It  is  formed  by  the  left  internal  jugular  vein  and  the  left  subclavian 
vein  at  the  inner  end  of  the  clavicle.  It  joins  the  right  innominate  vein  to 
form  the  superior  vena  cava.  The  innominate  veins  have  no  valves.  The 
radicles  of  the  left  innominate  vein  are,  (a)  left  vertebral,  (b)  left  internal 
mammary,  which  are  two  for  each  artery  but  unite  into  a  common  trunk 
before  entering  into  the  innominate  vein,  (c)  left  inferior  thyroid,  which  are 
three  or  four  in  number  pass  from  the  thyroid  venous  plexus  into  the  left  innom- 
inate vein,  (d)  the  left  superior  intercostal  receives  the  blood  from  the  second 
and  third  intercostal  spaces. 

The  one  on  the  right  side  passes  down  to  enter  the  vena  azygos  major, 
while  the  one  on  the  left  side  passes  across  the  arch  of  the  aorta  to  enter  the 
left  innominate  vein,  and  receives  the  left  bronchial  vein.  The  highest  inter- 
costal vein,  which  comes  from  the  first  intercostal  space,  empties  into  the  cor- 
responding vertebral  or  innominate  vein. 

The  superior  vena  cava  is  formed  by  the  two  innominate  veins  behind  the 
junction  of  the  first  right  costal  cartilage  with  the  sternum.  It  is  about  three 
inches  long  and  passes  clown  into  the  right  auricle  opposite  the  upper  border 
of  the  third  right  costal  cartilage.  This  vein  has  no  valves.  Its  radicles  are, 
(a)  pericardiac,  (b)  mediastinal,  (c)  vena  azygos  major.  It  collects  the  blood 
from  the  upper  half. of  the  body. 

When  the  blood  is  given  off  from  the  thoracic  aorta  into  the  intercostal 
arteries,  it  comes  back  by  the  intercostal  veins,  which  would  have  no  place  to 
empty  unless  there  was  a  special  provision  made  for  them.  They  cannot  empty 
into  the  heart,  and  the  inferior  vena  cava  has  no  length  above  the  Diaphragm, 
and  the  superior  vena  cava  is  too  high  for  most  of  them,  so  they  empty  into 
veins  called  azygos  veins  which  connect  the  superior  and  inferior  vena  cava. 
The  azygos  veins  have  no  valves,  but  their  tributaries  do  have  valves.  The 
azygos   veins  are:     (Plate  CXCV). 

1.  The  vena  azygos  major,  also  called  right  azygos  vein.  This  vein  com- 
mences at  the  first  or  second  lumbar  vertebra  by  a  branch  from  (a)  right  lum- 
bar veins,  (b)  or  by  a  branch  from  the  righl  renal  vein,  (c)  or  by  a  branch  from 
the  inferior  vena  cava.  After  passing  through  the  aortic  opening  in  the  Dia- 
phragm, it  passes  to  the  fourth  dorsal  vertebra  along  the  right  side  of  the  ver- 
tebral column  and  ends  in  the  superior  ven  cava  just  before  it  enters  the  per- 
icardium.     Its  radicle.-  are.  (a)  the  lower  ten  intercostal  veins  on  the  righl  side, 


4M  ANATOMY    IX    A    NUTSHELL. 

(in  vena  azygos  minor  from  the  Left  side,  (c)  oesophageal,  pericardiac,  and  medias- 
tinal veins,  (d)  the  right  bronchial  vein,  (e)  the  right  superior  intercostal  vein. 

2.  The  vena  azygos  minor,  also  called  left  lower  or  smaller  azygos  vein. 
This  vein  is  formed  by  a  branch  from  (a)  the  lumbar  veins,  (b)  or  from  the  left 
renal  vein.  After  passing  through  the  left  cms  of  the  Diaphragm,  it  passes 
along  the  left  side  of  the  vertebral  column  ami  at  the  ninth  dorsal  vertebra 
passes  to  the  right  behind  the  thoracic  aorta  and  thoracic  duct  to  end  in 
the  vena  azygos  major.  1 1 >  radicles  are,  (a)  four  or  five  lower  intercostal  veins 
cf  the  left  side,  (b)  some  (esophageal  and  mediastinal  veins. 

3.  The  left  upper  azygos  vein,  also  called  vena  azygos tertius.  The  radicles 
of  this  vein  are  from  the  intercostal  spaces  between  the  left  superior  intercostal 
vein  and  the  highest  radicle  of  the  vena  azygos  minor.  These  radicles  join  to 
form  a  main  trunk,  which  empties  into  the  vena  azygos  major  or  the  vena  azygos 
minor.  Somtimes  this  vena  azygos  tertius  is  wanting,  then  the  left  superior 
intercostal  vein  takes  its  place. 

The  bronchial  veins  from  the  right  side  empty  into  the  vena  azygos  major; 
while  those  of  the  left  side  open  into  the  left  superior  intercostal  or  vena  azygos 
tertius. 

For  veins  of  the  abdomen  see  page  186. 


LESSON  CLVII. 
The  Portal  System  of  Ykixs.     (Plates  CXXXVIII.) 

The  portal  system  collects  the  blood  from  the  digestive  tract  and  from  the 
spleen.  The  veins  of  this  system  form  the  portal  vein  which  enters  the  liver 
and  breaks  up  into  branches  like  an  artery  into  the  substance  of  the  liver. 
This  system  consists  of: 

1.  The  inferior  mesenteric  vein,  which  drains  the  blood  from  the  rectum, 
sigmoid  flexure,  and  the  descending  colon.  This  vein  empties  into  the  splenic 
vein  after  passing  behind  the  transverse  pari  of  the  duodenum  and  the  pancreas 
and  over  the  left  kidney.  Its  hemorrhoidal  radicles  inosculate  with  the  luemor- 
rhoidal  branches  of  the  internal  iliac. 

2.  The  superior  mesenteric  vein  collects  the  blood  from  the  small  intestine, 
the  caecum,  the  ascending  colon,  and  transverse  colon.  The  radicles  of  this 
vein  correspond  with  the  branches  of  the  superior  mesenteric  artery,  just  as 
the  radicles  of  the  inferior  mesenteric  correspond  to  the  branches  of  the  in- 
ferior mesenteric  artery.  This  vein  passes  in  front  of  the  transverse  portion  of 
the  duodenum  and  behind  the  pancreas  to  join  the  splenic  vein  at  the  upper 
binder  of  the  pancreas  where  it  forms  the  portal  vein. 

3.  The  splenic  vein  commences  in  the  hilum  of  the  spleen  by  five  or  six 
branches  which  unite  to  form  one  main  funk.  It  now  passes  below  the  splenic 
artery  and  behind  the  upper  border  of  the  pancreas  in  front  of  the  abdominal 
aorta  to  join  the  superior  mesenteric  vein. 

I.  The  gastric  vein,  also  called  coronary,  is  a  large  vein  which  passes  along 
the  lesser  curvature  of  the  stomach  to  the  cardiac  end  where  it  receives  radicles 


ANATOMY    IX    A    NUTSHELL. 


485 


from  the  oesophagus  and  then  passes  behind  the  lesser  sac  of  the  peritoneum 
into  the  portal  vein. 

.").  The  portal  vein  is  formed  by  the  splenic  vein  and  the  superior  mesenteric 

vein  behind  the  neck  of  the  pancreas.  It  passes  behind  the  first  part  of  the 
duodenum  and  then  in  the  lesser  omentum  to  the  transverse  fissure  of  the  liver. 
It  now  divides  into  right  and  left  branches  for  the  right  and  left  lobes  of  the 
liver  and  also  gives  ;i  branch  to  the  Spigelian  lobe.  For  the  further  subdivi- 
sion of  the  portal  vein  see  page  190. 

The  portal  vein   most   always  receives  the  cystic   vein,   although   it    may 
sometimes  end  in  the  right  branch  of  the  portal  vein. 

PLATE  CCLIX. 


VERTICAL       PLATE 


INFUNDIBULIIM 


CRIBRIFORM     PLATE 

Superior  View  of  the  Ethmoid. 

The  veins  of  the  heart  are: 

1.  The  great  cardiac  vein  (coronary  vein)  commences  at  the  apex  of  the 

heart  and  passes  to  the  base  of  the  ventricles  in  the  anterior  interventricular 
groove.  From  here  it  passes  to  the  left  in  the  auriculo-ventricular  groove  to 
the  back  pari  of  the  heart  where  it  opens  into  the  coronary  sinus.  Its  opening 
has  a  pair  of  valves.  Its  radicles  are.  (a)  those  winch  drain  the  right  ventricle, 
(b)  those  from  the  left  ventricle,  (c)  those  from  the  left  auricle.  These  radicles 
have   valves. 

2.  The  posterior  cardiac  vein  (the  middle  cardiac  vein)  commence-  at  the 
apex  of  the  heart  and  passes  along  the  posterior  interventricular  groove  to 
empty  into  the  coronary  sinus,  where  it  has  a  valve.  1 1>  radicles  are.  (a)  those 
from  the  posterior  surface  of  the  left  ventricle,  (b)  those  from  the  posterior 
surface  of  the  right   ventricle. 

3.  The  left  cardiac  veins  collect  the  blood  from  the  posterior  surface  of 
the  left  ventricle  and  open  into  the  coronary  sinus.  There  are  three  or  four 
of  these. 


186  ANATOMY    IN    A  NUTSHELL. 

1.  The  anterior  cardiac  veins  collect  the  blood  from  the  anterior  surface  of 
the  right  ventricle  and  empty  into  the  lower  part  of  the  righl  auricle.  There 
are  three  or  four  of  these  veins,  and  the  largest  one,  which  is  called  the  vein 
of  Galen  passes  along  the  right  border  of  the  heart. 

5.  The  right  coronary  vein  (small  coronary)  empties  into  the  coronary 
>inus  after  passing  between  the  righl  auricle  and  the  right  ventricle.  Its  rad- 
icle- are,  (a)  from  the  hack  part  of  the  right  auricle,  (h)  from  the  hack  part  of 
the  right  ventricle. 

6.  Venae  Thesesii,  also  called  venae  cordis  minimse,  open  by  small  orifices 
on  the  inner  surface  of  the  right  auricle.  These  orifices  are  called  foramina 
Thebesii. 

7.  The  coronary  sinus  is  a  dilatation  situated  in  the  posterior  part  of  the 
hit  auriculo-ventricular  groove.  It  receives  all  the  veins  just  mentioned  ex- 
cept the  vena1  Thebesii,  and  it  also  receives  the  oblique  vein  of  Marshall,  which 
is  from  the  back  part  of  the  left  auricle.  This  vein  empties  into  the  right  auricle 
of  the  heart  between  the  inferior  vena  cava  and  the  auriculo-ventricular  open- 
ing. It  is  guarded  by  the  valve  of  Thebesii  (coronary).  All  these  veins  of  the 
heart,  which  empty  into  the  coronary  sinus  have  valves  except  the  oblique 
vein  of   Marshall. 

Tuk  veins  of  Spinal  Column  and  Cord. 

The  veins  of  the  spinal  column  and  cord  are:     (Plates  CI-CII.) 

1 .  Dorsi-spinal  veins,  which  collect  the  blood  from  the  back  on  either  side 
of  the  spinous  processes.  These  veins  form  a  great  plexus,  which  join  the 
veins  in  the  spinal  canal  by  branches  which  perforate  theligmenta  subflavaand 
by  other  branches  which  pass  through  the  intervertebral  foramina.  These 
veins  end  in  the  vertebrals  in  the  neck,  in  the  intercostal  veins,  and  in  lumbar 
and  sacral  veins  in  their  respective  regions. 

2.  Meningo-raehidian  veins,  which  are  situated  in  the  spinal  canal,  form 
two  greal  columns,  (a)  the  anterior  longitudinal  spinal  veins  which  pass  from 
the  foramen  magnun  to  the  base  of  the  coccyx.  There  are  two  of  these  anterior 
longitudinal  spinal  columns,  one  on  each  side  of  the  posterior  surface  of  the 
bodies  of  the  vertebras.  The  radicles  of  these  veins  are  venae  basis  vertebrarum. 
These  veins  communicate  with  the  dorsi-spinal  veins,  vertebral  veins,  inter- 
costal  veins,  Lumbar  ami  sacral  veins,  (b)  The  posterior  longitudinal  spinal 
veins  are  situated  along  the  posterior  border  of  the  spinal  canal.  They  com- 
municate freely  with  the  anterior  ones,  the  dorsi-spinal  veins,  vertebral  veins, 
intercostal  veins,  lumbar  veins  and  sacral  veins.  The  meningo-raehidian  veins 
are  not  of  uniform  caliber  and  communicate  freely  with  one  another,  thus  form- 
ing sort  of  a  plexus. 

3.  Venae  basis  vertebrarum  pass  from  the  posterior  surface  of  the  vertebrae 
to  join  the  transverse  trunk  connecting  the  anterior  spinal  veins.  They  collect 
the  blood  from  the  substance  of  the  hone  and  are  similar  to  the  veins  of  the 
diplce  found  in  the  hones  of  the  cranium. 

4.  The  medulli  spinal  veins  collect  the  blood  from  the  substance  of  the  cord 
which  forms  a  venous  plexus  around  the  entire  surface  of  the  cord  between 


ANATOMY    IN    A    NUTSHELL.  IS', 

the  arachnoid  and  pia  mater.  In  the  upper  part  of  the  neck  these  veins  empty 
into  the  inferior  cerebellar  veins  or  the  inferior  petrosal  sinus.  Below  this 
they  empty  into  the  veins  of  the  spinal  canal.  None  of  the  spinal  veins  have 
valves. 


LESSON  CLVIII. 

Veins  of  Diplce. 

These  veins  lie  between  the  two  plates  of  the  bones  of  the  cranium  and  can 
be  seen  by  removing  the  outer  plate  of  the  skull.  They  are,  (1)  the  frontal, 
which  empties  into  the  supraorbital  vein,  (2)  the  anterior  temporal  which  joins 
the  deep  temporal  vein,  (3)  posterior  temporal  which  joins  the  lateral   sinus, 

(4)  the  occipital  which  joins  the  occipital  vein  or  lateral  sinus. 

Emissary  veins  are  small  veins  which  pass  through  foramina  in  the  bones  of 
the  cranium  to  connect  the  sinuses  with  the  external  veins  of  the  head.  The 
principal  ones  are  as  follows:  (1)  One  which  passes  thorugh  the  parietal  for- 
amen to  connect  the  veins  of  the  scalp  with  the  superior  longitudinal  sinus. 
(2)  One  which  passes  through  the  mastoid  foramen  to  connect  the  posterior 
auricular  vein  or  occipital  vein  with  the  lateral  sinus.  (3)  One  which  passes 
through  the  anterior  condyloid  foramen  to  connect  the  vertebral  vein  and  deep 
veins  of  neck  with  occipital  sinus.  (4)  One  which  passes  through  the  posterior 
condyloid  foramen  to  connect  the  lateral  sinus  with  the  deep  veins  of  the  neck. 

(5)  One  which  passes  through  the  foramen  ovale.  (6)  Two  or  three  which 
pass  through  the  middle  lacerated  foramen.  (7)  One  which  passes  through  the 
foramen  of  Vesalius.  The  fifth,  sixth,  and  seventh  all  connect  the  cavernous 
sinus  with  pterygoid  and  pharyngeal  plexuses.  (8)  One  which  passes  through 
the  carotid  canal  to  connect  the  cavernous  sinus  with  the  internal  jugular  vein. 

Cerebral  Veins. 

The  cerebral  veins  havethin  coatsandno  muscular  coat  or  valves.  They  are 
divided  into  a  superficial  set  and  a  deep  set.  Under  the  superficial  set  we  have 
(1)  superior  cerebral  veins,  which  are  lodged  in  the  fissures  on  the  cerebral  sur- 
face and  pass  forward  and  inward  to  the  superior  Longitudinal  sinus,  (2)  The 
median  cerebral  veins  which  collect  the  blood  from  the  convolutions  of  the 
mesial  surface  of  the  hemispheres.  These  veins  empty  into  the  superior  veins 
or  into  the  inferior  longitudinal  sinus. 

(3)  Inferior  cerebral  veins  collect  the  blood  on  the  lower  pari  of 
the  outer  and  on  the  under  surface  of  the  cerebral  hemisphere.  Under  these 
veins  we  have,  (a)  middle  cerebral  which  runs  along  the  fissure  of  Sylvius  on 
the  under  surface  of  the  temporal  lobe  and  empties  into  the  cavernous  sinus. 
(b)  the  great  anastomotic  vein  of  the  Trolard  runs  along  the  horizontal  Limb 
of  the  fissure  of  Sylvius  and  empties  into  the  anterior  part  of  the  cavernous 
sinus,  (c)  the  other  veins  on  the  under  surface  of  the  brain  empty  into  the  super- 
ior petrosal  sinus   and   lateral   sinus. 


488 


ANATOMY    IN    A    NUTSHELL. 


Under  the  deep  set,  we  have  (1.)  Venae  Galeni,  which  are  two  in  number. 
Thrv  are  formed  by  the  vena  corporis  striata  and  vena  choroidea.  They  pass 
hack  and  onl  of  the  transverse  fissure  to  enter  the  straight  sinus.  These  two 
veins  generally  unite  into  one  vein,  just  before  the  entrance  into  the  straight 

sinus.  (2.)  The  basilar  vein  is  formed  by  the  junction  of  the  deep  Sylvian  vein, 
inferior  striate  vein,  and  anterior  cerebral  veins.  It  now  passes  backward  over 
the  cms  cerebri  to  enter  the  vein  of  Galen  just  before  its  junction  with  the  vein 
of  the  opposite  side.  The  cerebellar  veins.  Under  these  we  have,  (1)  superior 
qnes,  which  pass  forward  and  inward  to  end  in  the  straight  sinus  and  the  veins 
of  Galen,  but  some  of  them  pass  outward  to  the  lateral  and  the  superior  petrosal 
sinus,  (2)  the  inferior  cerebellar  veins  end  in  the  lateral  sinus,  superior  petrosal 
sinus,    and    occipital    sinus. 

The  veins  of  the  medulla  oblongata  and  pons  end  in  the  inferior  petrosal 
sinus  and  lateral  sinus. 

PLATE  CCLX. 


WITH  LACHRYMAL 


WITH  SUP. 
MAXILLARY.  1 


ARTICULATES  WITH   ETHMOID. 
MAXILLARY  PROC. 
ARTIC.  WITH  PALATE 

POSTERIOR 
END. 

Inferior  Turbinated  Bone. 


WITH  LACHRYMAL. 


LESSON   CL1X. 
The  Sinuses  of  the  Dura  Mater.     (Plates  CLXXVIII-CLXXIX.) 

The  sinuses  of  the  dura  mater  are  as  follows: 

1.  The  superior  longitudinal  sinus  commences  at  the  foramen  caecum  and 
passes  along  the  upper  border  of  the  falx  cerebri  to  end  in  the  torcular  Her- 
ophili,  where  ii  receives  the  occipital  sinus  and  the  straight  sinus.  The  blood 
which  passes  through  the  superior  longitudinal  sinus  and  the  occipital  sinus 
turns  to  the  righl  at  the  torcular  Herophili  to  pass  into  the  right  lateral  sinus, 
while  the  blood  from  the  straight  sinus  passes  into  the  left  lateral  sinus.  How- 
ever, this  may  be  vice  versa.  At  the  foramen  caecum  a  small  vein  com- 
municates with  the  veins  of  the  nasal  fossa'  in  children.  This  sinus  on  cross 
section  is  triangular  with  apex  below  next  to  the  falx  cerebri.  The  chorda' 
Willisii  arc  fibrous  glands  which  constrict  this  sinus  and  take  the  place  of  valves. 
Most  of  the  radicle-  of  this  sinus  pass  into  it  in  such  a  manner  that  the  blood 
is  received  at  righl  angles  to  or  againsl  the  current  in  the  sinus.  It  receives 
veins  from  the  diploe  and  the  dura  mater,  the  superior  cerebral  veins,  and  veins 
from  the  pericranium  niter  passing  through  the  parietal  foramina. 


ANATOMY    IN    A    NUTSHELL.  489 

The  torcular  Herophili  is  a  dilatation  at  the  point  on  the  eight  side  of  the 
internal  occipital  protuberance  where  the  superior  Longitudinal,  occipital  and 
straight  sinuses  meet. 

2.  The  inferior  longitudinal  sinus     passes  along  the  lower  border  of  the 

falx  cerebri.  It  receives  veins  from  the  falx  cerebri  and  also  some  from  the 
sagittal  surface  of  the  hemispheres.  It  ends  in  the  straight  sinus,  ami  on  cross 
section  is  circular.  This  sinus,  as  well  as  the  preceding  one.  increases  in  size 
from  before  backward. 

3.  The  straight  sinus  connects  the  inferior  longitudinal  sinus  with  the 
superior  longitudinal  sinus  and  is  situated  at  the  junction  of  the  falx  cerebri 
with  the  tentorium  cerebelli.  The  inferior  longitudinal  sinus,  venae  Galeni, 
and  superior  cerebellar  veins  empty  into  it. 

4.  and  5.  The  lateral  sinuses  are  two  in  number  and  are  situated  where 
the  tentorium  cerebelli  joins  the  bone.  The  right  one,  after  receiving  the  blood 
from  the  superior  longitudinal  and  occipital  sinus,  passes  to  the  light  as  far  as 
the  petrous  portion  of  thetemporal  bone.  It  then  passes  downward  and  in- 
ward to  the  jugular  foramen,  where  it  receives  the  inferior  petrosal  sinus  to 
make  the  jugular  vein.  It  also  receives  the  superior  petrosal  sinus  at  the  base 
of  the  petrous  portion  of  the  temporal  hone.  The  left  lateral  sinus  has  a  sim- 
ilar description  but  receives  the  blood  from  the  straight  sinus.  It  occasionally 
receives  the  blood  from  the  superior  longitudinal  and  occipital  sinus,  and  then 
the  right  lateral  sinus  receives  the  blood  from  the  straight  sinus. 

6.  and  7.  The  occipital  sinus  which  is  the  smallest  of  these  sinuses,  may 
be  double.  It  is  situated  where  the  falx  cerebelli  joins  the  hone,  ami  as  said 
before,  it  empties  into  the  torcular  Herophili. 

These  seven  sinuses  are  situated  on  the  upper  and  back  part  of  the  skull, 
while  the  remaining  sinuses  of  the  dura  mater  are  situated  at  the  base  of  the 
skull. 

8.  and  9.  The  cavernous  sinuses  pass  from  the  sphenoidal  fissure  to  the 
apex  of  the  pelrous  portion  of  the  temporal  hone.  They  are  formed  by  the 
ophthalmic  vein  and  end  by  dividing  into  the  superior  and  inferior  petrosal 
sinuses.  In  each  cavernous  sinus  the  following  structures  are  found;  (a)  The 
third  cranial  nerve,  (b)  the  fourth  cranial  nerve,  (c)  the  ophthalmic  division 
of  the  fifth  cranial,  (e)  the  sixth  cranial,  (f)  the  internal  carotid  artery.  For 
position  of  these  structures  in  this  sinus  see  plate  CCXXXII.  The  facial  vein 
communicates  with  this  sinus  through  the  ophthalmic  vein.  The  circular  >inm 
connects  the  two  cavernous  sinuses. 

10.  The  circular  sinus  surrounds  the  hypophysis.  The  anterior  segment 
of  this  circle  is  larger  than  the  posterior  one.  One  or  the  other  of  these  seg- 
ments may  be  absent. 

11.  and  12.  The  superior  petrosal  sinuses  are  two  in  number,  one  on 
either  side,  and   they  connect    the  cavernous  with  the  lateral  sinus.      They  are 

situated  along  tin'  superior  border  of  the  petrous  portions  of  the  temporal 
bone.  Veins  fromtympanic  cavity,  some  cerebellar  vein-  and  inferior  cerebral 
Veins,  pass  into  it . 


4'. M)  ANATOMY    IN    A    NUTSHELL. 

13.  and  14.  The  inferior  petrosal  sinuses  pass  from  the  cavernous  sinus 
to  the  jugular  foramen  where  they  join  the  lateral  sinus  to  make  the  internal 
jugular  vein.  They  arc  situated  where  the  posterior  border  of  the  petrous  por- 
tion of  the  temporal  bone  joins  the  basilar  process  of  the  occipital. 

15.  The  transverse  siims  (basilar  sinus)  connects  the  two  inferior  petrosal 
sinuses.     It  passes  over  the  basilar  process  of  the  occipital  bone. 

The  Muscles  of  the  [schio-rectal  Region.     (Plate  CCLXXI.) 

Corrugator  cutis  ani. — Description. — This  muscle  radiates  from  the  ori- 
fice of  the  anus  and  is  a  thin  involuntary  muscle. 

<  Origin. — From  the  true  skin  externally  from  the  anus. 

Insertion. — Into  the  submucous  tissue  internally. 

A.CTION. — To  raise  the  skin  in  ridges  around  the  anus. 

Nerve  Supply     Sympathetic  nerve. 

Blood  Supply. — Inferior  hemorrhoidal. 

External  sphincter  ani. — Description. — This  muscle  surrounds  the  margin 
of  the  anus  and  is  elliptical  in  shape  and  thin  and  flat  in  form.  It  is  about  an 
inch  broad  opposite  tin1  anus,  and  from  its  anterior  to  its  posterior  extremity 
it  is  about  three  inches.      It  consists  of  two  planes  of  muscular  fibers. 

Origin. — From  the  tip  of  coccyx  by  a  narrow  tendon  and  from  super- 
ficial fascia  in  front  of  bone. 

Insertion. — Into  the  central  tendons  of  perineum  where  it  joins  with  the 
Transversus  perinaei,  Levator  ani.  and  Accelerator  urinae. 

Action.  -To  close  anus. 

Nerve  Supply. — From  the  anterior  division  of  the  fourth  sacral  and  in- 
ferior lnemorrhoidal  branch  of  the  internal  pudic  nerve. 

Blood  Supply. —  Inferior  hemorrhoidal  from  internal  pudic. 

Internal  sphincter  ani. — Description. — This  muscle  surrounds  the  lower 
part  of  the  rectum  for  about  an  inch.  It  is  composed  of  involuntary  muscu- 
lar fibers. 

A'  HON.-  -To  close  the  amis. 

Nerve  Supply. — Hsemorrhoi  lal. 

Blood  Supply.—  Inferior  hemorrhoidal  from  internal  pudic. 

Levator  ani.  Description. — This  muscle  which  is  thin  and  broad  is  sit- 
uated on  the  side  of  the  pelvis.  It  helps  to  support  the  viscera  in  the  pelvic 
cavity.  Sometimes  the  anterior  portion  of  this  muscle  is  separated  from  the 
posterior  portion  by  connective  tissue,  and  then  it  is  called  the  Levator  pros- 
tatas. 

Origin.  From  the  posterior  surface  of  the  body  and  ramus  of  the  os 
pubis  on  the  outer  side  of  the  symphysis.  Also  from  the  inner  surface  of  the 
spine  of  the  ischium  and  from  the  fascia  between  these  points. 

Insertion.  I  1  I  The  posterior  fibers  are  inserted  into  the  sids  of  the  apex 
of  the  coccyx,  and  those  fibers  just  in  front  of  these  mute  with  those  of  the 
opposite  side  extending  between  the  coccyx  and  the  margin  of  the  anus.  (2) 
The  middle  fibers,  which  form  the  greater  portion  of  the  muscle,  are  inserted 


ANATOMY    IN    A    NUTSHELL. 


491 


into  the  sides  of  the  rectum  blending  with  the  fibers  of  the  sphincter  muscles. 
(3)  The  anterior  fibers,  which  are  the  longest,  descend  upon  the  side  of  the 
prostate  gland  to  join  beneath  it  with  fibers  of  the  opposite  side,  and  also  blend- 
ing with  fibers  of  the  External  sphincter  and  Transversus  perinaei  a1  the  central 
tendon. 

Action. — It  is  a  muscle  of  forced  expiration.  It  also  supports  the  Lower 
end  of  the  rectum,  vagina,  and  bladder  during  efforts  of  expulsion. 

Nerve  Supply. — Branch  from  the  anterior  division  of  the  fourth  sacral 
and  a  branch  from  fhe  pudic  nerve  which  sometimes  comes  from  the  perineal 
or  from  the  inferior  hemorrhoidal  division. 

Blood  Supply. — Internal  pudic. 

Coccygeus. — Description. — This  muscle  is  situated  parallel  to  the  Levator 
ani  but  behind  it.  Its  upper  border  is  separated  from  the  lower  border  of  the 
Pyriformis  muscle  by  the  internal  pudic  vessels  and  nerves. 

PLATE  CCLXI. 


ANTERIOR 
BORDER. 


GROOVE  FOR 
SEPTAL  CARTILAGE 


ALA. 


P031.  POST.  SUP. 

BORDER.     )  Wk    I        VIEW. 

Ha 


GROOVE  FOR  NASO- PALATINE 
NERVE 


The  Vomer. 


ALA. 


Origin. — From  the  apex  of  the  spine  of  the  ischium  and  from  the  lesser 
sacro-sciatic  ligament. 

Insertion. — Into  the  margin  of  the  coccyx  and  side  of  lower  piece  of 
sacrum. 

Action. — Raises  and  supports  coccyx. 

Nerve  Supply. — Branch  from  the  fourth  and  fifth  sacral  nerves. 

Blood  Supply. — Internal  pudic. 


LESSON    CLX. 

Muscles  of  the  Perineum  in  the  Mali:.     (Plate  CCLXXI.) 

Transversus   perinsei. — Description.     This    muscle,    which    passes    across 

the  back  part  of  the  perineal  space,  is  a  narrow  muscular  slip. 

Origin. — From  the  inner  and  forepart  of  the  tuberosity  of  the  ischium   by 
a  small  tendon. 

Insertion. — Into  the  central  tendon  of  the  perineum. 

Nerve  Supply. — Perineal  branch  of  the  internal  pudic. 

Blood  Supply. — Internal  pudic. 


492  ANATOMY    IN    A    NUTSHELL. 

Accelerator  urinae. — ( Bulbo-cavernosus-Ejaculator  seminis.) — Descrip- 
tion. -This  muscle  is  situated  in  the  middle  line  of  the  perineum  just  in  front 
of  the  anus.  It  consists  of  two  similar  parts  united  in  the  middle  line  by  a 
tendinous  raphe. 

Origin.  From  the  central  tendon  of  the  perineum,  and  from  the  median 
raphe  in  trout. 

Insertion.— Into  the  anterior  surface  of  the  triangular  ligament  into  the 
hull)  and  adjacent  parts  of  the  corpus  spongiosum,  and  into  the  tunica  albu- 
genia  of  corpora  cavernosa. 

Action.— To  empty  the  urethra  and  assist  the  erector  penis. 

Nerve  Supply.  —Perineal  branch  of  the  internal  pudic. 

Blood  Supply. — Superficial  perineal  from  internal  pudic. 

Erector  penis. —  ( [schio-cavernosus.) — Description. — This  muscle  covers 
part  of  the  cms  penis  and  is  situated  on  either  side  of  the  lateral  boundary  of 
the  perineum.  This  muscle  is  broad  in  the  middle  and  narrow  at  the  extrem- 
ities. 

Origin. — From  the  inner  surface  of  the  tuberosity  of  the  ischium,  from 
the  surface  of  the  cms,  and  from  the  adjacent  portion  of  the  ramus  of  the  ischium. 

[nsertion. — Into  the  sides  and  into  the  under  surface  of  the  crus  penis 
by  an   aponeurosis. 

Action". — By  compressing  the  crus  penis,  it  retards  the  blood  through  the 
veins  and  in  this  manner  keeps  the  organ  erect. 

Nerve  Supply. — Perineal  branch  of  internal  pudic. 

Blood  Supply.— Superficial  perineal  from  internal  pudic. 

Compressor  urethra'. — (Constrictor  urethra'. ) — DESCRIPTION. — This  muscle 
is  situated  between  the  two  layers  of  the  triangular  ligament  and  surrounds  the 
membranous  portion  of  the  urethra. 

Origin.— From  the  junction  of  the  rami  of  the  os  pubis  and  ischium,  ex- 
tending to  half  an  inch  or  more. 

[nsertion.  Each  portion  of  this  muscle  divides  into  two  fasciculi  which 
surround  the  urethra  from  the  prostate  gland  behind  to  the  bulbous  portion  of 
the  urethra  in  front.  They  mute  at  the  upper  and  lower  surfaces  of  this  tube 
with  the  muscle  of  the  opposite  side. 

Action.  These  muscles  acting  together  assist  expelling  the  fluids  and 
compressing  the  membranous  portion  of  the  urethra. 

Nerve  Supply.— Perineal  branch  of  the  internal  pudic. 

Blood  Supply. — Superficial  perineal  from  internal  pudic. 


LESSON  CLXI. 
Mcs<  lesofthe  Perineum  ixthk  Female.     ( Plate  CCLXXI.) 

Transversus  periiuei.  DESCRIPTION. — This  is  a  small  muscular  slip  in  the 
female  which  passes  across  the  back  part  of  the  perineal  space. 

Okioiw  From  the  inner  and  forepart  of  the  tuberosity  of  the  ischium  by 
a  small  tendon. 


ANATOMY  IN  A  NUTSHELL.  41)o 

Insertion. — Into  the  central  tendon  of  the  perineum. 

Action. — This  muscle  with  its  fellow  fixes  the  central  tendon. 

Nerve  Supply.- — Perineal  branch  of  internal  pudic. 

Blood  Supply. — Superficial  perineal  from  internal  pudic. 

Sphincter  vagina. — Description.— The  Sphincter  vagina  which  surrounds 
the  orifice  of  the  vagina  is  the  homologue  of  the  Accelerator  mime  in  the  male. 

Origin. — Posteriorly  from  the  central  tendinous  part  of  the  perineum 
where  it  blends  with  the  External  sphincter  aid. 

Insertion.  —  Into  the  corpora  cavernosa  of  the  clitoris,  and  a  fasciculus 
passes  over  the  body  of  the  clitoris  to  compress  its  dorsal  vein. 

Action. — To  diminish  the  orifice  of  the  vagina. 

Nerve  Supply. — Perineal  branch  of  the  internal  pudic. 

Blood  Supply. — Superficial  perineal  from  internal  pudic. 

Erector  clitoridis. — Description. — This  muscle  is  the  homologue  of  the 
Erector  penis  in  the  male,  but  is  a  smaller  muscle. 

Origin. — From  the  inner  surface  of  the  tuberosity  of  the  ischium  behind 
the  eras  clitoridis,  and  also  from  the  surface  of  the  eras  and  the  adjacent  por- 
tion of  the  ramus  of  the  ischium. 

Insertion. — Into  the  sides  and  upper  surface  of  the  eras  clitoridis. 

Action. — To  maintain  the  organ  erect  by  pressing  on  the  eras  clitoridis 
and  retarding  the  return  of  blood  through  the  veins. 

Nerve  Supply. — Perineal  branch  of  the  internal  pudic. 

Blood  Supply. — Superficial  peiineal  from  internal  pudic. 

Compressor  urethra. — (Constrictor  urethra). — 

Origin. — From  the  margin  of  the  descending  ramus  of  the  os  pubis. 

Insertion. — The  fibers  from  the  front  part  of  the  muscle  cross  the  sub- 
pubic arch  in  front  of  the  urethra  to  blend  with  its  fellow  of  the  opposite  side, 
while  fibers  from  the  posterior  portion  pass  inward  to  blend  with  the  walls  of 
the  vagina   behind  the  urethra. 

Action. — To  expell  the  mine  and  assist  in  erection. 

Nerve  Supply. — Perineal  branch  of  the  internal  pudic. 

Blood  Supply. — Superficial  perineal  from  internal  pudic. 


LESSON  CLXII. 

The  Perineum.    (Plate  CCLXIX.) 

The  word  Perineum  is  \\>n\  in  three  different  senses.  (  1  )  il  includes  the 
entire  outlet  of  the  pelvis,  which  extends  from  the  apex  of  the  sub-pubic  arch 
in  front  to  the  tip  of  the  coccyx  behind,  and  laterally  between  the  tuberischii. 
(2)  Il  is  the  part  of  the  pelvic  outlet  in  fnint  of  a  line  connecting  the  tuberi- 
schii.  This  is  called  the  true  perineum,  while  the  pari  behind  this  line  is  called 
the  anal,  ischio-rectal.  or  false  perineum.  (3)  In  the  surgical  and  obstetrical 
sense  of  the  word  the  term  may  include  in  the  female  all  the  deeper  par  t  between 
the  posterior  wall  of  the  vagina  and  the  anterior  wall  of  the  ledum.  Tin-  is 
called  the  perineal  body. 


494 


ANATOMY    IN    A    NUTSHELL. 


The  ischio-rectal  fossae  are  situated  on  each  side  of  the  lower  end  of  the 
recutm,  having  on  the  outer  side  of  each  fossa,  the  tuberosity  of  the  ischium, 
The  ischio-rectal  fossa  is  in  the  form  of  a  pyramid  with  its  apex  corresponding 
to  the  junction  of  the  Levator  ani  and  Obturator  muscles.  Its  base  is  between 
the  anus  and  the  tuberischii.  It  is  bounded  on  the  inner  side  by  the  Sphincter 
ani.  Levator  ani.  and  Coccygeus  muscles;  and  behind  by  the  edge  of  the  Gluteus 
maximus  and  the  great  sacro -sciatic  ligament.  It  is  the  site  of  abscesses 
and  is  filled  with  a  mass  of  adipose  connective  tissue.     (Plate  CCLXX.) 

THE  FAsei.K  OF  THE  PERINEUM   ARE: 

1.  The  superficial  layer  of  the  superficial  fascia,  which  is  continuous  with 
the  sub-cutaneous  fascia  of  the  thighs,  is  thick  and  loaded  with  fat.  This  is 
the  lowest  of  all  the  fascia  of  the  perineum. 

PLATECCLXII. 


ORBITAL      PROCESS 
ORBITAL       SURFACE 


SPHENOIDAL    SURFACE 


POSTERIOR     NASAL    SPINE 


AZYGOS  UVULAE 


The  Palate  Bone,  Posterior  View. 

2.  The  deep  layer  of  the  superficial  fascia  is  called  Colles'  fascia.  It  is 
not  thick,  but  very  strong.  It  is  attached  posteriorly  to  the  perineal  ledge. 
anteriorly  it  becomes  continuous  with  the  external  fascial  investment  of  the 
scrotum  ami  the  fascial  covering  of  the  penis.  It  extends  laterally  to  the  rami 
of  the   pubis   ami    ischium.     Some   anatomists   call    this   fascia   the  anterior 

LEAFLET    OF    THE    TRIANGULAR     LIGAMENT. 

3.  Tin'  anterior  Layer  of  the  deep  perineal  fascia  is  triangular  in  shape  like 
Colles'  fascia,being  bounded  on  either  side  by  the  ramus  of  the  pubis  and  ischium 

and  extending  in  from  from  the  pubic  arch  and  sub-pubic  ligament  to  the  per- 
ineal Ledge  p0Steri6rly.  Some  anatomists  call  this  THE  MIDDLE  LEAFLET  OF 
'IH1-;   TRIANGUL  \l<    LIG  V.MENT. 

4.  The  posterior  layer  of  the  deep  perineal  fascia  is  called  by  some  anato- 
mists THE  POSTERIOR  LEAFLET  OF  THE  TRIANGULAR  LIGAMENT  and  has  the  same 
attachments  as  the  middle  leaflet  of  the  triangular  ligament. 


ANATOMY    IX    A    XUTSHELL.  495 

The  "white  line,"  or  arcus  tenmbtEus,  extends  from  the  inner  aspect 
of  the  spine  of  the  ischium  to  the  back  of  the  os  pubis,  external  to  the  symphysis, 
and  is  formed  by  a  thickening  of  the  obturator  fascia  where  the  fascia  of  Leva- 
tor ani  muscle  meets  the  obturator  fascia.  This  line,  of  course,  is  Dot  straigb.1 
because  it  comforms  to  the  curve  of  the  pelvic  wall. 

Buck's  fascia  is  a  continuation  of  Colles'  fascia  which  extends  forward 
upon  the  penis,  which  it  invests  completely,  as  far  as  the  gland.-. 

The  triangular  ligament  of  the  urethra.  One  set  of  anatomists  describe 
the  anterior  layer  of  the  deep  perixeai.  fasci  \  as  the  triangular  ligament, 
while  another  set  include  the  posterior  layer  of  the  deep  perineal  fasci  \. 
thus  making  two  layers  of  the  triangular  ligament.  Still  a  third  set  of  anat- 
omists include  Colles'  fascia  in  the  triangular  ligament,  thus  making  three 
leaflets  in  the  triangular  ligament.  Where  these  three  triangular  leaflets  meet 
posteriorly  is  called  the  perineal  ledge,  and  as  they  pass  forward  towards 
the  symphysis  pubis  there  are  two  spaces  between  these  three  leaflets.  The 
one  between  the  first  two  leaflets  is  called  the  superficial  perineal  inter- 
space, and  contains  the  following  structures: 

1.  The  crura  of  the  corpora  cavernosa. 

2.  The  bulb  of  the  corpus  spongiosum. 

3.  Scattered  fibers  of  the  Superficial  transverse  periinei  muscle. 

4.  Arteiies  of  the  corpora  cavernosum  and  dorsal  vessels  of  the  penis. 

5.  Dorsal  nerves  of  the  penis. 

6.  Superficial  perineal  vessels  and  nerves. 

The  space  between  the  second  and  third  leaflets  of  the  triangular  ligament 
is  called  the  deep  perineal  interspace  and  contains: 

1.  The  membranous  urethra. 

2.  C'owper's  glands. 

3.  Internal  pudic  arteries. 

4.  Pudic  veins. 

5.  The  pudic  lymphatics. 

6.  Dorsal  nerves  of  the  penis. 

7.  The  deep  Transverse  peiinaei  and  Compressor  urethra   muscles. 

The  central  tendon  of  the  perineum  is  about  half  an  inch  in  front  of  the 
amis,  in  the  middle  of  the  perineal  ledge,  and  is  the  place  where  the  External 
sphincter  ani  and  Accelerator  mime  and  Transverse  perinaei  muscles  meet. 

Alcock's  canal  is  about  two  inches  in  length  and  is  formed  by  a  delamina- 
tion  of  the  obturator  fascia.  It  is  situated  on  the  outer  wall  of  the  ischio- 
rectal fossa,  extending  from  the  lesser  sacro-sciatic  foramen  to  the  lower  border 
of  the  triangular  ligament.  The  internal  pudic  vessels  and  nerve  pass  through 
this  canal.      (Plate  CCLXX.) 

The  pelvic  fascia  lines  the  cavity  of  the  pelvis  and  at  the  white  line  it  divides 
into  (1 )  rk<  Tn-\  ESU  \\.  FASCIA,  which  is  called  visceral  layer  of  the  pelvic  fascia. 
This  layer  descends  from  the  white  line  over  the  Levator  ani  muscle,  over  the 
prostate  gland.  rentum,  vesiculae  seminales  and  the  bladder.  It  forms  the  true 
ligaments  of  the  bladder.     (2)  The  obturator   fascia,   which   is  called   the 


mm;  anatomy  in  a  nutshell. 

parietal  layer  of  the  pelvic  fascia.  This  layer  passes  from  the  white  line  on  the 
pelvis  tn  cover  the  Obturator  interims  muscle,  and  above  Alcock's  canal  gives 
off  the  anal  fascia  (ischio-rectal)  over  the  lower  surface  of  the  Levator  ani  mus- 
cle. This  fascia  with  the  corresponding  fascia  of  the  opposite  side  forms  the 
deep  superior  layer  of  the  triangular  ligament. 


LESSON  CLXIII. 
Lymphatic  System.  (Plates  CCLXXXIX-CCXC.) 
"niphatic  system  consists  of  lymphatic  vessels,  and  lymphatic  nodes. 
The  lymphatic  vessels  of  the  small  intestine  are  called  lacteals  or  chyliferous 
vessels  because  during  the  process  of  digestion  they  contain  chyle  which  they 
carry  into  the  blood  through  the  thoracic  duct.  The  lymphatic  vessels  are 
present  in  all  the  pari  of  the  body  except  the  hair,  nails,  cuticle,  and  cartilage. 
The  lymphatic  system  is  in  the  form  of  the  human  body.  It  commences  in 
microscopic  space-  which  join  one  another  to  make  larger  spaces  until  they 
finally  form  the  two  lymphatic  ducts,  the  righl  and  the  left.  The  left  one  is 
called  the  thoracic  duct  because  it  passes  through  the  thorax.  It  collects  lymph 
from  all  the  body  except  the  right  half  of  the  head,  the  right  half  of  the  thorax. 
and  the  upper  surface  of  the  liver,  and  the  right  arm.  The  lymph  in  these 
structures  just  named  pass  into  the  right  lymphatic  duct.  This  right  lympha- 
tic duct  is  about  half  an  inch  long  and  empties  into  the  tight  subclavian  vein. 
The  lefi  lymphatic  or  thoracic  duct  is  about  eighteen  inches  long  and  passes 
upon  the  vertebral  column  behindthe  archof  the  aorta,  ii  finallyends  in  the  left 
subclavian  vein.  This  duct  may  be  double  for  part  of  its  way  or  throughits  en- 
ure course,  and  it  may  empty  into  the  vena  azygos  major.  It  has  constric- 
tions through  its  entire  course  and  a  double  valve  at  its  termination. 

Every  cell  in  the  body  is  surrounded  by  lymph  and  is  therefore  an  aquatic 
animal.  These  cells  receive  their  food  from  the  lymph  into  which  they  also 
throw    their    waste    products. 

The  lymphatic  vessels  in  the  body  are  in  two  sets,  superficial  and  deep. 
The  superficial  lymphatics  pass  just  under  the  skin  with  the  superficial  veins 
and  they  pierce  the  deep  fascia  to  join  the  deep  lymphatic  vessels.  The  deep 
lymphatics  although  not  so  numerous  as  the  superficial  ones  are  larger  and 
accompany  the  deep  blood  vessels.  The  lymphatic,  absorbent,  or  conglobate 
nodes  are  small  bodies  of  adenoid  tissue  which  the  lymphatic  vessels  pass 
through  on  their  way  to  the  thoracic  and  lymphatic  duct-.  These  nodes  vary 
in  size  from  very  small  ones  which  are  microscopic,  to  large  one-  which  are 
aboui  the  si/.e  of  a  small  bean.  Their  color  is  pinkish-gray,  but  those  in  the 
bronchial    region    are   a    darker   color. 

The  lymphatics,  like  veins,  have  three  coats,  but  the  smallest  lymphatic 
vessels  have  one  coat  which  is  composed  of  epithelial  cells.  Those  vessels 
which  have  three  coat.-  have  the  following  arrangement,  (1)  an  inner  coat  of 
epithelium  and  a  -mull  amount  of  yellow  fibrous  tissue:  (2)  \  MIDDLE  COAT 
composed  of  muscular  tissue  and  yellow  fibrous  tissue:  (3)  AX  OUTER  COAT 
which  consists  of  white  fibrous  tissue  and  a  little  of  the  yellow  fibrous  tissue. 
All  three  of  these  coat-  pu1   together  are  transparent.     Valves  are  present  in 


ANATOMY  IX  A  NUTSHELL. 


497 


lymphatic  vessels  to  prevent  the  backward  how  of  the  lymph.  They  are  formed 
by  folds  of  the  lining  membrane  and  their  position  is  marked  by  a  circular  con- 
striction. 

The  thoracic  duct  has  three  coats,  (1)  an  internal  or  endothelial,  (2)  a 
middle  of  white  connective  tissue,  (3)  an  external  of  areolar  tissue.  There 
are  numerous  valves  in  the  thoracic  duct  especially  at  its  upper  end,  and  there 
is  a  pair  at  its  termination  to  prevent  blood  from  entering  the  duct. 

The  kelations  of  the  thoracic  duct  are: 

.Behind. — (1)  The  body  of  the  second  lumbar  vertebra,  (2)  Bodies  of  the 
seven  lower  thoracic  vertebra1,  (3)  Anterior  common  ligament,  (4)  Lower 
right  intercostal  arteries.  (.1)  Vena  azygos  minor,  ((>)  Vena  azygos  tertius,  (7) 
Upper  thoracic  vertebrae. 

Ox  Right  Side. — (1)  Right  cms  of  the  Diaphragm,  (2)  Vena  azygos  major, 
(3)  Right  pleura,  (4)  (Esophagus. 

In  Front. — (1)  Aorta  and  right  cms  of  the  Diaphragm,  (2)  Pericardium, 
(3)  (Esophagus,  (4)  Arch  of  the  aorta,  (5)   First  portion  of  subclavian  artery. 

On  Left  Side. — (1)  Aorta,  (2)  Left  pleura,  (3)  Vena  azygos  minor.  (4) 
Vena  azygos  tertius. 


PLATE  CCLXIII. 


ORBITAL      PROCESS 
ETHMOIDAL     SURFACE 


SUPERIOR    MEATUS 

SPHENO-PALATINE 

FORAMEN^ 


SPHENOIDAL   PROCESS 'J<C<\  \ 

'fyli  I  >;MEA 

/o\V  <v 


ORBITAL      SURFACE 

MAXILLARY     SURFACE 


(MC-*TUS   c,  *|fc-MAXILURY    PROCESS 

INF.     TURBINATED  ft,  .'  s  /^  _j 

.x  j\\  INFERIOR    /  = 
MEATUS  A 
ARTICULATES   WITH    "        / 

ffWm 


HORIZONTAL      i    PLATE 
ARTICULATES        WITH     VOMER     AND    OPPOSITE     HONE 

The  Lateral  View  of  the  Palate  Bone. 

The  receptaculum  chyll  is  the  beginning  of  the  thoracic  duct.  It  isan  irregu- 
lar, sacculated  and  fusiform  sac.  It  has  no  valves  in  it.  and  its  dimensions  are 
one  and  a  half  by  three-quarters  of  an  inch.  It  is  situated  in  fronl  of  tin"  sec- 
ond hunbai'  vertebra. 

A  lymphatic  node  consists  of  an  outer  pari  called  a  capsule,  which  is  made 
of  white  fibrous  tissue  and  a  small  amount  of  smooth  muscular  tissue.  From 
the  inner  surface  of  t  his  capsule  trabecular  pass  towards  the  center  of  the  node. 


498  ANATOMY    IN    A    NUTSHELL. 

These  trabecule  arc  broad  at  the  attachment  of  the  capsule  but  small  in  the 
central  portion.  The  outer  portion  of  the  node  is  called  cortex  and  the  inner 
portion  is  called  medulla.  These  trabeculse  form  numerous  divisions  in  the 
node,  and  these  divisions  are  partly  filled  with  pulp  The  space  between  the 
pulp  and  the  division  wall  is  called  the  lymph  sinus  and  is  crossed  by  a  net- 
work of  adenoid  reticular  tissue.  This  pulp  is  a  mass  of  leucocytes.  The 
hilum  is  a  notch  where  the  arteries  enter  and  the  veins  and  efferent  vessels  Leave 
the  node.     These  nodes  make  white  blood  corpuscles. 

There  are  aboul  seven  hundred  lymphatic  nodes  in  the  body  andtheyare 
all  situated  beneath  the  deep  fascia  except  the  superficial  inguinal  nodes. 


LESSON  CLXIV. 

The  superficial  lymphatic  vessels  of  the  upper  extremity  pass  from  the  tips 
of  the  fingers  towards  the  shoulder  with  the  superficial  veins.  Those  on  the 
inner  side  of  the  arm  run  with  the  ulnar  veins  towards  the  elbow  then  with  the 
basilic  vein  to  the  axillary  glands  and  deep  vessels.  Those  on  the  outer  side  of 
the  arm  run  with  the  radial  veins  to  the  elbow,  and  at  this  point  some  join  the 
basilic  group,  while  others  run  with  the  cephalic  vein  to  the  axillary  nodes. 
A  few  i^  this  last  set  pass  between  the  Deltoid  muscle  and  the  Pectoralis  major 
to  the  subclavian  nodes. 

The  deep  lymphatic  vessels  of  the  upper  extremity  pass  with  the  deep  blood 
vessels.     They  accompany  the  following    arteries  in  the  forearm:     (t)   radial, 

(2)  ULNAK.  (3)  ANTERIOR  INTEROSSEOUS,  (4)  POSTERIOR  INTEROSSEOUS.   They 

communicate  with  the  superficial  lymphatic  vessels  at  intervals.  They  ac- 
company the  brachial  artery  from  the  elbow  and  pass  through  the  axillary  and 
subclavian  nodes  to  the  thoracic  duct  on  the  left  side,  while  those  on  the  right 
side  pass  to  the  right   lymphatic  duct. 

The  superficial  lymphatic  nodes  of  the  upper  extremity  are  not  numerous. 
In  the  cubital  fossa  there  are  two  or  three  and  above  the  internal  condyle  near 
the  basilic  vein  there  is  one  or  two. 

The  deep  lymphatic  nodes  of  the  upper  exremity  are  found  along  the  radial 
and  ulnar  vessels.  A  few  small  ones  are  found  along  the  inner  side  of  the 
brachial  artery,  and  one  or  two  just  above  the  inner  condyle.  There  arc  ten 
ortwelve  around  the  axillary  vessels  which  drain  the  front  of  the  chest  and  the 
skin  of  the  back.  The  subclavian  nodes  are  two  or  three  which  are  connected 
with  the  axillary  nodes  and  deep  cervical  nodes.     They  lie  under  the  clavicle. 

The  superficial  lymphatic  vessels  of  the  lower  extremity  lie  in  the  supei- 
ficial  fascia.  They  are  divided  into  two  groups,  (1)  a  large  internal  group 
which  follows  the  internal  saphenous  vein  to  the  vertical  set  of  the  superficial 
inguinal  nodes.  From  these  superficial  inguinal  nodes  some  efferent  vessels 
pass  through  the  cribriform  fascia  and  femoral  sheath  to  a  node  in  the  femoral 
canal  by  which  it  communicates  with  the  vessels  of  the  trunk,  and  others  pass 
through  the  fascia  lata  to  the  deep  inguinal  nodes.  (2)  An  external  group, 
which  is  smaller  and  is  situated  on  the  outer  side  of  the  foot,  sends  one  set  of 
vessels  across  the  tibia  just  below  the  knee  to  join  the  internal  group,  while  the 


ANATOMY  IN  A  NUTSHELL.  499 

other  set  passes  with  the  external  saphenous  vein  to  join  the  popliteal  nodes. 
The  deep  lymphatic  vessels  of  the  lower  extremity  accompany  the  following 

arteries:  (1)  anterior  tibial,  (2)  posteriok  tibial,  (3)  perineal,  to  the 
popliteal  nodes.  From  the  popliteal  nodes  they  pass  with  the  femoral  vein 
to  the  deep  inguinal  nodes,  and  then  under  Poupart's  ligamenl  to  the  nodes 
around  the  external  iliac  vessels.  The  lymphatic  vessels  in  the  gluteal  region 
pass  to  the  "luteal  nodes  in  the  great  sacro-sciatic  foramen.  The  lymphatic 
vessels  of  the  ischiatic  region  have  a  similar  course. 

The  superficial  lymphatic  nodes  of  the  lower  extremity  are,  (1 )  eighl  or  ten 
superficial  inguinal  nodes  which  lie  just  under  the  skin.  They  consisl  of 
two  sets,  (a)  the  upper  oblique  along  Poupart's  ligament,  which  drains  the 
scrotum,  penis,  abdominal  wall,  perineal  and  gluteal  regions,  and  urethral 
mucous  membrane,  (b)  The  vertical  set  which  surrounds  the  saphenous  open- 
ing and  receive  the  superficial  vessels  of  the  lower  extremity. 

The  deep  lymphatic  nodes  of  the  lower  extremity  are,  (1)  one  or  two  anter- 
ior tibial,  which  are  placed  beside  the  anterior  tibial  artery  on  the  upper  part 
of  the  interosseous  membrane,  (2)  four  or  five  popliteal,  which  are  placed 
around  the  popliteal  vessels,  (3)  the  deep  inguinal,  which  are  placed  under 
the  deep  fascia  around  the  femoral  vessels.  These  communicate  with  the 
superficial  inguinal  nodes  through  the  saphenous  opening.  (4)  The  gltjte  \i.. 
which  follow  their  corresponding  vessels  into  the  great  sacro-sciatic  foramen 
above  the  P)rriformis  muscle.  (5)  Ischiatic  which  follow  their  corresponding 
vessels  into  the  sacro-sciatic  foramen  below  the  Pyriformis  muscle. 


LESSON   CLXV. 

The  superficial  lymphatic  vessels  of  the  pelvic  and  abdominal  walls  pass 

with  the  superficial  blood  vessels.  (1)  Those  below  the  umbilicus  pass 
with  the  superficial  epigastric  vessels  to  the  oblique  set  of  the  superficial  inguinal 
nodes.  (2)  A  DEEPER  SET  passes  with  the  deep  epigastric  vessels  to  the  ex- 
ternal iliac  nodes  which  form  a  chain  around  the  external  iliac  blood  vessels. 
Three  of  these  nodes  are  found  just  behind  the  crural  arch  which  communicates 
with  the  lumbar  nodes  above  and  with  the  inguinal  nodes  below.     (3)  Those 

FROM  THE   SIDES   OF  THE   LUMBAB    PART   OF  THE   ABDOMINAL  WALL   pass    with    the 

superficial  iliac  blood  vessels  to  the  oblique  set  of  the  superficial  inguinal  node-. 
lmt  most  of  them  pass  with  the  ilio-lumbar  and  lumbar  blood  vessels  to  the 
lateral  lumbar  nodes.  (4)  Those  of  the  gluteal  region  pass  around  the 
outer  side  of  the  nates  to  end  in  the  superficial  inguinal  nodes.  (">)  THOSE 
of  the  scrotum  A\D  perineum  pass  with  the  external  pudic  vessels  to  end  in 
the  superficial  inguinal  nodes.  (6)  Those  of  tin:  penis  end  in  the  superficial 
inguinal  nodes.  (7)  Those  which  drain  the  mucous  membrane  of  the 
labia,  NYMPH.E,  and  clitoris  in  the  female  end  in  the  oblique  set  of  the  super- 
ficial nodes. 

The  deep  lymphatic  vessels  of  the  pelvic  and  abdominal  walls  pass  with  the 
chief  biood   vessels  and  are,   (1)  those  which  accompany    the  gluteal  ves- 

BELS,    (2)    THOSE   WHICH    ACCOMPANY   THE    [SCHIATIC   VESSELS,    (•'))    THOSE    WHICH 


500 


ANATOMY  IX  A  NUTSHELL 


accompany  the  obturator  vessels.  All  these  pass  with  the  internal  iliac 
artery  to  join  the  Lumbar  mules.  (4)  Those  ok  tin:  penis  pass  with  the  internal 
pudic  vessels  to  join  the  internal  iliac  nodes. 

The  lymphatic  vessels  of  the  bladder  pass  through  its  mules  mi  the  pos- 
terior  surface  ami  join  the  lymphatic  vessels  from  the  prostate  gland  ami  seminal 
vesicles  pass  into  the  internal  iliac  nodes  which  surround  the  internal  iliac  blood 
vessels.  These  nodes  receive  radicles  corresponding  to  the  branches  of  the 
internal  iliac  artery  and  they  communicate  with  the  lumbar  nodes. 

The  lymphatic  vessels  of  the  rectum  pass  through  nodes  on  its  outer  wall 
and  in  the  meso-rectum.  They  empty  into  the  sacral  nodes  which  occupy  the 
sides  and  t'roiii  of  the  sacrum  in  the  meso-rectal  fold. 


PLATE  CCLXIV 


SUPERIOR  TURBINATED 


INFERIOR  TURBINATED 

The  Meatuses. 


Tin'  lymphatic  vessels  of  the  uterus  are.  (1)   SUPERFICIAL  ONES  which  are 

situated  under  the  peiitoneum  and  (2)  deep  ones  situated  in  the  substance 
of  the  uterus.  Those  from  the  vagina  and  from  the  cervix  pass  into  the  sacral 
nodes  and  internal  iliac  nodes,  while  those  from  the  body  and  fundus  pass  into 
the -broad  ligamenl  to  join  those  from  the  ovaries,  broad  ligaments,  and  Fallo- 
pian tubes  to  pa--  with  the  ovarian  vessels  to  the  lumbar  nodes.  These  lum- 
bar nodes  are  situated  around  the  common  iliac  vessels,  the  aorta,  and  inferior 
vena  cava  on  the  front  of  the  lumbal-  vertebrae.  They  receive  vessels  from  the 
lower  extremities,  pelvis,  testes,  ami  some  of  the  abdominal  viscera.  They 
unite  with  the  lacteal-  to  help  form  the  thoracic  duct.  The  lateral  lumbar 
nodes  are  situated  between  the  transverse  processes  of  the  vertebra?  behind  the 


ANATOMY    IN    A    NUTSHELL.  501 

Psoas  magnus  muscle  and  help  to  drain  the  spinal  canal,  posterior  and  lateral 
abdominal  walls. 

The  lymphatic  vessels  of  the  testicle  are.  (1)  superficial  which  arc  from 
the  surface  of  the  tunica  vaginalis,  and  (2)  deep  ones  which  are  from  the 
epididymis  and  body  of  the  testis.      They  empty  into  the  lumbar  nodes. 

The  lymphatic  vessels  of  the  kidney  are,  (1)  superficial  and  ('_')  deep. 
These  two  vessels  mute  at  the  hilum  to  join  the  vessels  from  the  ureter  and 
suprarenal  capsule.     They  end  in  the  lumbar  nodes. 

The  lymphatic  vessels  of  the  stomach  are  two  set>.  (1)  SUPERFICIAL  ONES 
in  the  subserous  coat  and  (2)  deep  ones  in  the  submucous  coal.  The  ves- 
sels which  drain  both  surfaces  of  the  stomach  pass  alongthe  lesser  curvature  to 
end  in  nodes  at  the  pyloric  end  of  the  stomach.  Those  which  drain  the  fundus 
pass  to  the  splenic  nodes  and  those  which  pass  along  the  greater  curvature  of 
the  stomach  join  lacteals  at  the  root  of  the  mesentery. 

The  lymphatic  nodes  of  the  stomach  lie  within  the  lesser  omentum  and 
around  the  cardiac  and  pyloric  orifices  along  the  curvatures  of  the  stomach. 

The  lymphatic  vessels  of  the  spleen  are.  (1)  superficial  which  lie  under 
its  peritoneum,  and  (2)  deep  which  lie  in  its  substance.  They  end  in  the  thoracic 
duet  after  receiving  the  pancreatic  lymphatic  vessels. 

The  nodes  of  the  spleen  are  situated  in  its  hilum. 

The  lymphatic  vessels  of  the  small  intestine  are  called  lacteals  and  are,  (1) 
superficial  which  are  placed  between  the  layers  of  the  muscular  coat,  or 
between  the  nmscnlar  and  peritoneal  coats.  They  run  longitudinally.  (2) 
Deep  which  are  situated  in  the  submucous  tissue  and  run  transversely  with 
the  mesenteric  vessels.     These  empty  into  the  thoracic  duct. 

The  lymphatic  nodes  of  the  small  intestine,  called  mesentery  node-,  lie 
between  the  layers  of  the  mesentery,  and  they  are  about  one  hundred  and 
fifty  in  number.  They  vary  in  size  from  that  of  a  pea  to  that  of  a  small  almond, 
and  the  largest  ones  are  situated  near  the  duodenum  and  the  ilio-csecal  valve. 
In  these  positions  they  are  also  more  numerous. 

The  lymphatic  vessels  of  the  large  intestine  are  in  two  sets.  (1)  THOSE  of 
the  csecum,  ascending  colon,  and  transverse  colon  which  pass  to  the  mesenteric 
nodes,  and  (2)  those  of  the  descending  colon,  sigmoid  flexure,  and  rectum 
which  pass  to  the  lumbar  nodes. 

The  lymphatic  nodes  of  the  large  intestine  are  not  so  numerous  as  those  of 
the  small  intestine  and  are  very  few  along  the  transverse  colon.  They  are  -it- 
uated  upon  the  intestine  itself  or  along  the  vascular  arches  of  the  arteries. 

LESSON  CLXVI. 

The  lymphatic  vessels  of  the  liver  are  in  two  sets.  (1)   THE  SUPERFICIAL  SET 

which  lie  in  the  subperitoneal  areolar  tissue,  and  on  the  convex  surface  of  the 
liver.  Those  vessels  on  the  convex  surface  of  the  liver  are  divided  into  the 
following  groups,  (a)  those  branches  which  rnn  forward  ami  then  upward  in  the 

broad  ligamenl  pass  through  the  Diaphragm  to  the  anterior  mediastinal  node-.. 
These  anterior  mediastinal  nodes  are  situated  on  the  Diaphragm  in  front  of  the 


502  ANATOMY  IN  A  NUTSHELL. 

pericardium  and  around  the  greai  vessels  at  the  base  of  the  heart.  The  vessels 
from  the  liver  jus;  mentioned  which  pass  through  those  mediastinal  nodes  pass 
into  the  right  lymphatic  duct,  (b)  Those  vessels  winch  run  around  the  anterior 
margin  to  the  under  surface  of  the  liver  pass  to  nude-  in  the  lesser  omentum. 
Those  branches  which  pass  outward  to  the  right  lateral  ligament  pass  either 
through  the  Diaphragm  to  the  anterior  mediastinal  nodes  or  across  the  cms  of 
the  Diaphragm  to  the  anterior  mediastinal  nodes  or  across  the  cms  of  the 
Diaphragm  into  the  thoracic  duct,  (d)  Those  branches  which  run  outward 
from  the  left  lobe  to  the  left  lateral  ligament  and  then  through  the  Diaphragm 
to  the  anterior  mediastinal  nodes.  Those  superficial  lymphatic  vessels  which 
are  on  the  under  surface  of  the  liver  form  the  following  groups,  (a)  those  branches 
which  arise  to  the  right  of  the  "'all  bladder  pass  to  the  lumbar  nodes,  (b)  those 
branches  surrounding  the  gall  bladder  pass  to  the  nodes  in  the  lesser  omentum, 
and  (c)  those  branches  arising  to  the  left  of  the  gall  bladder  pass  either  to  the 
oesophageal  nodes  or  to  nodes  along  the  lesser  curvature  of  the  stomach. 

Tin:  DEEP  lymphatic  VESSELS  of  the  livee  pass  with  the  branches  of 
the  portal  vein,  hepatic  artery,  and  hepatic  duct  into  the  substance  of  the  liver. 
They  puss  from  the  liver  at  the  transverse  fissure  to  enter  nodes  which  are 
placed  along  the  lesser  curvature  of  the  stomach  and  behind  the  pancreas.  Or 
they  may  join  a  lacteal  before  entering  the  thoracic  duct. 

The  superficial  lymphatic  vessels  of  the  thoracic  wall  pass  across  the  Trape- 
zius and  Latissimus  dorsi  muscle.-  behind  and  the  Pectoralis  major  muscle  in 
front  to  end  in  the  axillary  nodes.  Most  of  those  from  the  mammary  gland 
pass  to  small  nodes  which  are  situated  along  the  lower  border  of  the  Pectoralis 
major  muscle  in  the  axilla,  however,  a  few  from  the  inner  side  of  mammary  gland 
pass  through  the  intercostal  spaces  to  the  anterior  mediastinal  node-. 

The  deep  lymphatic  vessels  of  the  thoracic  Avail  are.  (1)  intercostal  \  es- 
SELS  which  drain  the  Intercostal  muscles  and  pleura.  These  join  vessels  from 
the  buck  of  the  thorax  and  spinal  canal  which  entering  the  intercostal  nodes 
descend  on  the  spine  to  the  thoracic  duct.  The  intercostal  nodes  which  are 
small,  lie  on  each  side  of  the  spine  near  the  costo-vertebral  articulation,  and 
some  of  those  lying  between  the  Intercostal  muscles.  (2)  The  internal 
mammary  which  begin  on  the  abdominal  muscles  above  the  umbilicus  where  they 
communicate  with  the  epigastric.  They  pass  upward  through  the  Diaphrgam 
where  they  are  joined  by  the  intercostal  lymphatic  vessels  to  empty  into  the 
right  lymphatic  duct  on  the  right  side,  while  those  on  the  left  side  empty  into 
thoracic  duct.  (3)  The  lymphatic  \  essels  of  the  Diaphragm  empty  into  the 
anterior  mediastinal  and  internal  mammary  nodes  anteriorly,  and  into  the  in- 
tercostal and  posterior  mediastinal  nodes  posteriorly. 

The  internal  mammary  nodes  lie  at  the  anterior  end  of  each  intercostal 
-pan-  near  the  internal  mammary  vessels. 

The  posterior  mediastinal  nodes  lie  along  the  aorta  and  oesophagus,  and 
communicate  with  the  intercostal  nodes,  lumbar  nodes,  and  deep  cervical 
nodes. 

The  superficial  lymphatic  vessels  of  the  lung  form  a  minute  plexus  which 
covers  the  outer  surface  Of  the  lung  under  the  pleura,  while  the  deep  lymphatic 


ANATOMY  IX  A    NUTSHELL. 


503 


vessels  run  with  the  blood  vessels  along  the  bronchi.  The  lymphatics  of  the 
Lung  empty  into  the  bronchial  nodes,  which  lie  around  the  bifurcation  of  the 
trachea  and  the  root  of  the  lung.  Several  efferenl  vessels  pass  from  these  nodes 
to  the  tracheal  nodes  and  oesophageal  nodes  at  the  root  of  the  neck,  and  those 
on  the  right  side  empty  into  the  right  lymphatic  duct,  while  those  on  the  left 
side  empty  into  the  thoracic  duct. 

The  superficial  cardiac  lymphatic  vessels  lie  on  the  surface  of  the  heart  in 
the  subserous  or  areolar  tissue,  while  the  deep  cardiac  lymphatic  vessels  lie  in 
the  deeper  tissues.  These  vessels  accompany  the  coronary  vessels.  Those  of 
the  right  side  uniting  at  the  root  of  the  aorta  from  which  place  they  pass  upward 
over  the  arch  of  the  aorta  along  the  trachea  to  the  right  lymphatic  duct.  Those 
of  the  left  side  unite  at  the  base  of  the  heart  and  pass  along  the  pulmonary  artery 
to  nodes  at  the  root  of  the  arota.  and  after  ascending  along  the  trachea  pass  into 
the  thoracic  duct. 

The  thymic  vessels  pass  into  the  internal  jugular  veins  from  the  under  sur- 
face of  the  thymus  gland. 

The  lymphatics  of  the  oesophagus,  after  communicating  with  the  posterior 
mediastinal  nodes,  end  in  tin1  thoracic  duct. 


LESSON   CLXVII. 

The  superficial   lymphatic   vessels  of  the  scalp  are  as  follows:     (1)  Pos- 
terior  or  OCCIPITAL  vessels  which  follow  the  course  of  the  superficial  veins 

PLATE  CCLXV. 


Tiii';  Urixiferous  Turtles. 


downward  over  the  occipital  bone  to  the  occipital  nodes.  These  node-  are  also 
called  suboccipital  and  are  situated  just  below  the  superior  line  curved  of  the 
occipital  bone.  Their  radicles  are  from  the  back  of  the  bead,  and  the  vessels 
from  these  nodes  empty  into  the  superficial  Lymphatic  nodes  of  the  neck.  In 
secondary  syphilis  these  nodes  arc  enlarged.  (2)  POSTERIOR  AURICULAR  (pos- 
tero-lateral)  vessels  pass  downward  behind  the  ear  toend  in  the postero-auricu- 
lar  nodes,  also  called  Sterno -mastoid.  These  nodes  are  situated  over  the  in- 
sertion of  the  Stemo -cleido-mastoid  muscle.  The  vessels  which  Leave  these 
nodes  empty  into  the  superficial  cervical.  (•"»)  Temporal  lymphatic  vessels, 
also  called  antero-lateral,  pass  with  the  superficial  temporal  veinand  end  in  the 
parotid  lymphatic  nodes.       These  nodes  are  situated     over  the  parotid     gland 


504  ANATOMY  IX  A  NUTSHELL. 

and  sonic  of  them  are  in  the  substance  of  the  parotid  gland.  Their  radicles 
drain  part  ofthe  temple,  externa]  pails  of  the  eye  lid.  and  the  posterior 
pari  of  die  cheek.  The  vessels  which  leave  these  nodes  empty  into  (a)  sub- 
maxillary nodes,  (b)  some  of  them  in  the  superficial  cervical  nodes.  (4)  An 
anterior  or  frontal  set  pass  over  the  frontal  hone  and  empty  into  the 
buccal  ami  submaxillary  nodes.  The  buccal  Lymphatic  nodes  are  situated 
mi   the  surface  of  the  Buccinator  muscle. 

The  superficial  lymphatic  vessels  of  the  face  end  in  the  submaxillary  lym- 
phatic nodes.  These  nodes  are  situated  beneath  the  body  of  the  lower  jaw  in 
the  submaxillary  triangle  of  the  neck.     There  are  eight  to  twelve  of  these  nodes. 

Their  radicles  are,  (1)  FROM  THE  UPPER  AND  LOWER  LIPS  \\D  SIDE  OF  NOSE,  (2) 
FROM  THE  FLOOR  OF  THE  MOUTH,  (3)  FROM  FRONT  PART  OF  TONGUE,  (4)  FROM 
SUBLINGC  \l.  Wl>  SI  BM  VXILI.ARY  SALIVARY  GLANDS,  and  ("))  FROM  THE  ANTERIOR 
PART  OF  THE  CAROTID  LYMPHATIC  NODES.  The  vessels  that  leave  these  nodes 
empty  into  the  deep  cervical  lymphatic  nodes  and  also  into  the  superficial  lym- 
phatic   nodes. 

The  suprahyoid  lymphatic  nodes  are  two  or  three  in  number  and  are  sit- 
uated in  the  median  line  between  the  anterior  bellies  of  the  Digastric  muscles. 

The  superficial  lymphatic  vessels  of  the  neck  join  the  superfical  lymphatic 
vess<  Ls  of  the  seal])  and  face  and  upper  part  of  the  thorax.  They  empty  into 
the  superficial  cervical  lymphatic  nodes.  These  nodes  are  situated  between 
the  Platysma  myoides  muscle  and  the  deep  fascia  along  the  course  of  the  ex- 
ternal jugular  vein.  Small  lymphatic  nodes  are  found  anterior  to  these  between 
the  hyoid  bone  and  the  sternum,  also  posteriorly  over  the  Trapezius  muscle. 
The  radicle-  of  these  superficial  cervical  nodes  are,  (1)  thosk  from  the  occipital 

NODES,  (2)  THOSE  FROM  THE  POSTERIOR  AURICULAR  NODES,  (3)  SOME  FROM  THE 
PAROTID     \\D    SUBMAXILLARY    NODES, ,(4)    FROM  THE   INTEGUMENT   OF  THE    NECK 

AND  external  ear.  The  vessels  passing  from  these  nodes  end  in  the  deep 
cervical   lymphatic   nodes. 


LESSOX   CLXVIII. 

The  deep  lymphatic  vessels  of  the  head  and  neck  follow  the  course  of  the 
deep  arteries  and  end  in  the  deep  cervical  chain  of  lymphatic  nodes.     They 

an-  a-  follows:  (1)  meningeal  i.vMPHATic  vessels  which  pass  with  the  menin- 
geal arteries  through  foramina  at  the  base  of  the  skull  to  end  in  dee])  cervical 
nodes.  (2)  CEREBRAL  LYMPHATICS,  which  pass  with  the  internal  carotid  artery, 
bral  artery,  and  internal  jugular  vein  through  foramina  at  the  base  of  the 
skull  to  join  the  deep  lymphatic  nodes.  (3)  lymphatic  VESSELS  of  the  ORBIT 
follow  the  inferior  orbital  vein  into  the  spheno -maxillary  fossa  ami  fromhere 
they  follow  the  internal  maxillary  vein  and  empty  into  the  internal  maxillary 

nodes  and  deep  carotid   nodes,   (4)  THE  LYMPHATIC  VESSELS   FROM  THE  TEMPORAL 

FOSSA  wi>  ZYGOMATK  i  i  »SS  \  pass  through  the  internal  maxillary  nodes  to  join 
the  deep  cervical  nodes,  (5)  lymphatn  \  essels  from  the  inferior  of  the  nose 
end  in  the  lymphatics  of  the  pharynx  and  into  the  deep  cervical  nodes.  They 
communicate   with    the    subdural   lymph   space  and   the    subarachnoid  lymph 


ANATOMY  IX  A  NUTSHELL.  505 

space  by  means  of  the  lymph  spaces  which  surround  the  olfactory  nerves. 
(6)  Lymphatic  vessels  of  the  mouth  and  tongue.  Those  from  the  floor  of 
the  mouth  pass  into  the  submaxillary  lymphatic  nodes  after  passing  through  the 
Mylo-hyoid  muscle.  Those  from  the  lips  pass  into  both  the  submaxillary  and 
into  the  deep  cervical  nodes.  Those  deeply  situated  hi  the  check  and  in  roof 
of  mouth  join  the  internal  maxillary  lymphatic  nodes.  Those  on  the  tongue 
pass  with  the  ranine  vein  and  empty  into  the  deep  cervical  nodes,  after  passing 
through  small  lingual  nodes  in  the  Hyo-glossus  muscle.  Lymphatic  vessels  of 
the  front  part  of  the  tongue  pass  into  the  submaxillary  nodes  after  passing 
through  the  Mylo-hyoid  muscle.  (7)  The  lymphatic  vessels  i  >f  the  pharynx 
empty  into  the  deep  cervical  nodes,  but  those  from  the  upper  pari  of  the  pharynx 
first  pass  through  the  post-pharyngeal  node.  Lymphatic  vessels  of  the  tonsil 
empty  into  the  submaxillary  nodes.  (8)  The  lymphatics  of  the  larynx 
empty  into  the  deep  cervical  nodes.  (9)  The  lymphatics  vessels  of  the 
upper  part  OF  the  CESOPHAGUS  axd  trachea  open  into  the  deep  cervical  nodes. 
(10)  The  lymphatics  of  the  thyroid  gland  open  into  the  dee]»  cervical  nodes. 
The  deep  lymphatic  nodes  of  the  head  are,  (1)  the  lingual,  which  are  sit- 
uated on  the  outer  surface  of  the  Hyo-glossus  and  Genio -hyo-glossus  muscles. 
There  are  two  to  four  in  number  and  collect  the  lymph  from  the  upper  surface 
and  posterior  part  of  the  substance  of  the  tongue.  The  vessels  from  these  nodes 
empty  into  the  superior  nodes  of  the  deep  cervical  nodes.  (2)  The  [nternal 
maxillary  or  deep  facial  nodes  are  situated  behind  the  Buccinator  muscle  and 
are  three  to  six  in  number.     Their  radicles  arefrom  (a)  the  orbit,  (b)  the  nose, 

(c)  the  temporal  and  spheno-maxillary  fossaB,  (d)  the  upper  jaw.  (e)  the  palate, 
(f)  the  pharynx.  The  vessels  from  these  nodes  empty  into  the  superior  nodes 
of  the  deep  cervical  nodes.  (3)  The  post-pharyngeal  node  is  situated  near  the 
base  of  the  skull  on  the  Rectus  capitis  anitcus  major  muscle.  Its  radicles  are 
from  (a)  the  pharynx,  do  nose,  (c)  the  deep  prevertebral  muscles. 

The  deep  lymphatic  nodes  of  the  neck  are,  (1)  an  upper  ski  which  passes 
along  the  internal  jugular  vein  as  far  as  the  thyroid  cartilage.  This  set  of 
nodes  receives  radicles  from  the  (a)  inferior  of  the  cranium.  (In  from  the  deep 
muscle-  of  the  upper  part  of  the  neck,  (c)  from  the  internal  maxillary  glands, 

(d)  from  the  posterior  half  of  the  tongue,  (e)  from  the  middle  portion  of  the 
pharynx,  (f)  the  upper  part  of  the  larynx,  (g)  the  upper  part  of  the  thyroid 
gland,  (h)  and  some  of  the  vessels  from  the  submaxillary  nodes.  Vessels  from 
these  nodes  pass  downward  to  the  lower  deep  cervical  nodes.  (2)  A  lower 
set  which  follows  the  internal  jugular  vein  fr the  thyroid  cartilage  to  near  it- 
termination.  These  receive  radicles  from  (a)  the  lower  pari  of  the  neck,  (b) 
the  upper  set  of  lymphatic  node-,  (c)the  Lower  part  of  the  larynx,  (d)  lower 
pari  of  thyroid  gland,  (e)  the  upper  part  of  the  oesophagus  and  trachea,  (f) 
from  the  superficial  cervical  nodes.  The  vessels  which  leave  these  node-  end 
in  the  jugular  lymphatic  trunk  which  mute-  with  the  subclavian  lymphatic 
trunk  to  form  the  right  lymphatic  trunk  on  the  right  side  and  the  thoracic  duct 
on  the  left  side. 


506 


ANATOMY    IN    A    NUTSHELL 


LESSON   CLXIX. 
Frontal  Bone.     (Plates  GCXXXVII-CCXXXVIII.) 

The  frontal  bone  consists  of  two  main  parts,  a  vertical  or  frontal  por- 
noN  which  forms  the  forehead,  and  a  horizontal  or  orbito-nasal  portion 
which  forms  the  roofs  of  the  orbits  and  nasal  fossae. 

The  external  surface  of  the  vertical  portion  lias  the  following  points  for 
consideration : 

1.  Tin.  metopic  suture  (presenl  in  the  young)  is  situated  in  the  middle 
of  the  fn.nial  bone.     (Plate  CCXXXVIII.) 

2.  The  frontal  eminence  is  just  below  the  center  of  the  bOne  externally 
from   the   mid-lino. 

PLATE  CCLXVL 


?-     J^BERT.INT^J^g     CAV1TY 


RENAL     ARTERY 


!NFUNDIBUIU^ 

Sagittal  Section  of  the  Kidney. 

3.  The  arched  superciliary  ridge  is  below  the  frontal  eminence  and 
separated  from  it  by  a  groove.  This  ridge,  which  is  produced  by  the  frontal 
sinus,  is  more  disl  bid    internally. 

4.  The  glabella  or  nasal  eminence  is  between  the  superciliary  ridges  and 
-  continuous  with  them. 

5.  Tin  si  praorbital  ^rch  is  the  upper  margin  of  the  orbit  and  separates 
the  vertical  and  horizontal  portions  of  the  frontal  bone. 

6.  The  si  praorbital  mi  >t<  ii  or  foramen  is  at  the  junction  of  the  inner  and 
middle  thirds  <>f  this  arch.     It   transmits  the  supraorbital  vessels  and  nerve 


ANATOMY    IN  A    NUTSHELL.  507 

and  at  this  point  a  small  vein  from  the  diplce  passes  into  tin'  supraorbital  vein. 

7.  The  external  angular  process  is  the  end  of  the  supraorbital  arch 
and  is  well  marked.     It  articulates  with  the  malar  bone. 

8.  The  internal  angular  process  is  the  other  end  of  the  supraorbital 
arch  and  is  not  so  well  marked  as  the  external  angular  process.  It  articulates 
with  the  lachrymal  hone 

9.  The  temporal  ridges  run  upward  and  backward  from  the  external 
angular  process.  The  lower  ridge  gives  attachment  to  the  Temporal  muscle, 
and  the  upper  one  gives  attachment  to  the  temporal  fascia. 

10.  The  anterior  part  of  the  temporal  fossa  is  below  these  ridges  and 
gives  origin  to  part  of  the  Temporal  muscle. 

11.  The  nasal  notch  is  between  the  internal  angular  processes  and  artic- 
ulates with  the  two  nasal  bones  mesially  and  with  the  nasal  process  and  the 
superior  maxillary  bone  ext<  rnally.  |    [    P 

12.  The  nas\l  process  passes  from  this  notch  under  the  nasal  bones  and 
the  nasal  processes  of  the  superior  maxillary  bones. 

13.  The  nasal  spine  arises  from  the  under  surface  of  the  nasal  process 
and  joins  the  nasal  bones  in  front  and  the  perpendicular  plate  of  the  ethmoid 
behind  to  form  part  of  the  septum. 

The  internal  surface  of  the  vertical  portion  has  the  following  points  for 
consideration  : 

1.  A  vertical  groove  which  passes  along  the  middle  line  for  the  superior 
longitudinal  sinus,  and  the  edges  of  this  groove  give  attachment  to  the  falx 
cerebri. 

2.  The  frontal  crest  is  formed  by  the  edges  of  this  groove  muting  an- 
teriorly. 

3.  The  foramen  cecum  is  formed  by  a  notch  in  the  lower  end  of  the 
frontal  crest  by  its  articulation  with  the  ethmoid.  This  foramen  lodges  a  pro- 
cess of  the  falx  cerebri,  and  when  open  a  vein  from  the  nose  passes  through  it 
to  the  superior  longitudinal  sinus. 

4.  Eminences  and  depressions  are  found  on  this  surface  of  the  frontal 
bone  external  to  the  median  line  for  the  cerebral  convolutions. 

5.  Furrows  which  are  for  branches  of  the  anterior  meningeal  arteries. 

6.  Depressions  for  the  Pacchionian  bodies  are  near  the  vertical  groove. 
The  frontal  sinuses  are  two  spaces  at  the  anterior  inferior  part  of  the  bone 

between  its  layers.     They  are  lined  with  mucous  membrane  and  open  into  the 
middle  meatus  of  the  nose  by  the  ini'undibula. 

The  inferior  surface  of  the  horizontal  portion  has  the  following  point-  for 
consideration: 

1.  The  ETHMOID  NOTCH  separates  two  thin  plates  which  forms  the  vaull 
of  each  orbit.  This  notch  is  filled  by  the  cribriform  plate  of  the  ethmoid,  and 
edges  of  this  notch  present  half  cells  which  with  half  cells  of  the  ethmoid  make 
the  ethmoidal  cells. 

2.  The  lachrymal  fossa,  which  is  for  the  lachrymal  gland,  is  near  the 
external  angular  process. 

3.  A  depression  or  tubercle  for  the  fibrous  pulley  "\  the  Superior  oblique 
muscle  is  at  the  nasal  margin  of  this  surface. 


508  ANATOMY    IX    A    NUTSHELL. 

4.  A.NTERIOB  ETHMOIDAL  FORAMEN  is  for  the  anterior  ethmoidal  vessels 
and  nasal  branch  of  the  ophthalmic  nerve. 

POSTERIOB    ETHMOIDAL    FORAMEN   is   for   the   posterior  ethmoidal  vessels. 

The  superior  surface  of  the  horizontal  portion  is  convex  and  has  depressions 
and  eminences  for  the  frontal  convolutions,  also  grooves  for  branches  of  the 
anterior  and  middle  meningeal  arteries. 

*  Ossification.     This  hone  has  two  centers  of  ossification,  one  for  each  half. 

Ajrticulation.  It  articulates  with  the  following  hones:  (1)  the  two 
parietal,  (2)  the  sphenoid.  (3)  the  ethmoid.  (4)  two  nasal.  (5)  two  superior 
maxillary,  (6)  two  Lachrymal,  (7)  two  malar,  thus  making  twelve  bones. 

Attachment  of  Muscles.  —  It  has  three  pairs  of  muscles  attached  to  it. 
l     Corrugator  supercilii,    (2)  Orbicularis   palpebrarum,    (3)  Temporal. 

Blood  Supply.-  The  middle  and  small  meningeal  arteries  on  the  cerebral 
surface  and  the  frontal  and  supraorbital  on  the  outer  surface.  The  ethmoidal 
arteries  and  other  branches  of  the  ophthalmic  artery  pass  to  the  horizontal 
plate 

Corrugator  supercilii. — Description.  — This  muscle,  which  is  situated  be- 
neath the  Occipito- frontalis  and  Orbicularis  palpebrarum  at  the  inner  end  of 
the  superciliary  ridge,  is  small  and  pyramidal. 

Origin. — From  inner  end  of  the  superciliary  ridge  of  temporal  bone. 

[nsertion. — Into  the  deep  surface  of  the  skin  opposite  the  middle  of  the 
supraorbital  arch. 

A.CTION.  To  draw  the  eye  brow  downward  and  inward,  which  produces 
the  vertical  wrinkles  in  the  forehead. 

Nerve  Supply. — Temporal  branch  of  the  facial  nerve,  or  by  fibers  of  the 
third  nerve  which  join   this  nerve. 

Blood  Supply. — Supra-orbital  and  frontal  from  ophthalmic  artery. 

Orbicularis  palpebrarum.  -Description. — This  muscle,  which  surrounds 
the  circumference  of  the  orbil  and  eye  lids,  consists  of  an  orbicular  portion  and 
a  palpebral  portion. 

Origin  of  Orbicular  Portion. — (1)  From  internal  angular  process  of  the 
frontal  bone,  (2)  nasal  process  of  superior  maxillary  bone.  (3)  borders  and 
anterior  surface  of  the  tendo  oculi. 

[NSERTION.  Into  the  skin  of  the  eye  lids,  forehead,  temple,  and  cheek. 
ii-  upper  fibers  blending  with  the  Occipito-frontalis  and  the  Corrugator  super- 
cilii. 

Origin  <>v  Palpebral  Portion.  -  From  the  bifurcation  of  the  tendo  oculi. 
This  portion  is  thinner  and  paler  than  the  other  portion. 

INSERTION.  Into  ;i  raphe  on  the  outer  side  of  the  eye  lids,  the  external 
tarsal  ligament,  and  malar  bone. 

Ai  TION.       To    close    the    eye    lids. 

\u:\  i.  Supply.  Temporal  branch  of  facial  nerve  or  by  fibers  of  the  third 
nerve  which  join  this  nerve. 

Blood  Supply.  Supra-orbital,  frontal  from  ophthalmic,  and  branches 
from  the  temporal. 

Temporal.  Description.  -This  is  a  large  and  radiating  muscle  situated 
in   the  temporal   fossa. 


ANATOMY  IX  A  NUTSHELL. 


509 


Origin. — (1)  From  temporal  ridge,  (2)  temporal  fascia,  (3)  greater  part 
of  the  temporal  fossa. 

Insertion. — Into  the  inner  surface,  apex  and  anterior  border  of  the  cor- 
onoid  process  of  the  inferior  maxillary  bone. 

Action. — To  bring  the  incisor  teeth  together.     It  is  called  the  biting  muscle. 

PLATE  CCLXVII. 


v    X    A    xx    ^   \N    A\V    \     x) 


Ull 


W&: 


''I11'  WJ-): ?'''«■: 
.  i '■r'i *"/;'/'/'/.,' 

I,.',:. ''/.////.'»/, 

,.'l!;.,'|Mlir''//'/'J 

GLANSCLITORIOIS 

FRENULUM  CLITORIDlS 

.   ORIFICIUM    v\v  - 
URETHR/e  EXTERNUM 

LABIUM  MAdU&Xx  - 
, '.'.'  '  '•  x"Av  \V^^ 
LABIUM  MINUS V_V 


POST.  COMMISSURE 


:.\\H...\\-     <■ 


:"  ■>''•      •.>,_.,..-     v'  '  ANUS 

The  Female  External  Organs  of  Generation. 

Nerve  Supply. — Temporal  branches  of  the  inferior  maxillary  division  of 
the  fifth  nerve. 

Blood  Supply. — .Muscular  branches  from  the  second  portion  of  the  internal 
maxillary  artery. 


LESSON   CL  XX. 
The  Parietal  Bone.     (Plates  CCXXXIX-CCXL.) 
The  parietal  bone  has  two  surfaces,  fouh  borders,  and  four  angles  for 

consideration. 


510  ANATOMY    IN    A    NUTSHELL. 

The  external  surface  of  the  parietal  bone  has  the  following  points: 

1.  Parietal  emineni  e  near  the  center  of  the  bone  where  ossification  com- 
mences. 

2.  TWO  SEMICIRCULAR  TEMPORAL  RIDGES  which  are  about  two-fifths  of  an 
inch  apart  ami  arc  continuous  with  the  ridges  on  the  frontal  bone,  and  like 
those  on  the  frontal  bone  give  attachment  to  the  Temporal  muscle  and  to  the 
temporal  fascia. 

:!.  The  surface  below  these  ridges  gives  attachment  to  part  of  the 
Temporal  muscle. 

4.  The  parietal  foramen  is  near  the  superior  border  and  transmits  a 
vein  to  the  superior  longitudinal  sinus.  Occasionally  a  branch  of  the  occipital 
artery  passes  through  this  foramen.     This  foramen  is  inconstant. 

The  internal  surface  of  the  parietal  hone  is  concave1  and  has  the  following 
points: 

1.  Eminences  and  depressions  for  the  cerebral  convolutions. 

2.  Furrows    for  the  middle  meningeal  artery. 

3.  A  oi;oo\  i..  which  with  its  fellow.  Lodges  the  superior  longitudinal  sinus. 
There  i-  also  a  groove  for  the  lateral  sinus  at  the  posterior  inferior  angle. 

The  superior  border  is  dentated  and  with  its  fellow  forms  a  sagittal 
suture,  which  is  a  synarthrosis  joint.  This  border  is  the  longest  and  thickest 
of  the  four  borders. 

The  anterior  border  joins  the  frontal  bone  and  helps  to  form  the  coronal 
suture. 

Tin-;  POSTERIOR  BORDER  joins  the  occipital  bone  and  helps  to  form  the 
Lambdoid  suture. 

Tin:  [NFERIOR  BORDER  is  divided  into  the  following  parts,  (a)  the  anterior. 
which  is  overlaped  by  the  tip  of  the  greater  wing  of  the  sphenoid,  (b)  the  middle 
part  which  i>  overlaped  by  the  squamous  portion  of  the  temporal  bone,  and 
(c)  the  posterior  pari  which  articulates  with  the  mastoid  process  of  the  temporal 
bone. 

Tin.  INTERIOR  SUPERIOR  ANGLE  is  the  point  where  the  two  parietal  bones 
meel  the  frontal  hone.  This  is  the  location  of  the  anterior  fontanelle  which 
is  called  the  -oft  spol  in  the  baby's  head. 

Tin-:  posterior  superior  axoi.k  is  the  point  where  the  two  parietal  bones 
ami  the  occipital  hone  meet-.      This  is  the  location  of  the  posterior  fontanelle. 

Tin.  posterior  [NFERIOR   vngle  joins  the  mastoid  process  of  the  temporal 

hone. 

'I'm.  INTERIOR  [NFERIOR  ANGLE  joins  the  frontal  hone  and  greater  wing  of 
the  sphenoid  hone. 

OSSIFICATION. — This  bone  ossifies  from  one  center. 

Artn  i  lation.  It  articulates  with.  (1)  the  opposite  parietal  bone.  (2)  the 
occipital  bone.  (3)  the  frontal.  (4)  the  temporal,  and  (5)  the  sphenoid,  thus 
making  five  bone-. 

Attachment  of  Mi  s<  les.  This  bone  has  but  one  muscle  attached  to  it, 
the  Temporal.      See   page   508 

Blood  Supply.     Middle  meningeal,  occipital,  supraorbital  arteries. 


ANATOMY    IN    A    NUTSHELL.  511 

LESSON    CLXXI. 
The  Occipital  Bone.     (Plates  CCXLI-CCXLIL) 
The  occipital  bone  is  situated  at  the  posterior  and  inferior  region  of  the 
cranium  and  is  trapezoidal  in  form.     This  bone  is  curved  upon  itself. 

The  external  surface  is  convex  and  has  the  following  points  for  consideration  : 

1.  The  external  occipital  protuberance  is  situated  midway  between 
the  superior  point  of  the  hone  and  the  foramen  magnum.  It  gives  attachment 
to  the  ligamentum  nuchse. 

2.  The  external  occipital  crest  is  a  vertical  ridge  extending  from  the 
external  occipital  protuberance  to  the  foramen  magnum.  Tins  also  gives  at- 
tachment to  the  ligamentum  nucha?. 

3.  The  superior  curved  line  extend-  outward  on  each  side  from  the 
external  occipital  protuberance.  This  line  gives  attachment  to  the  Trapezius 
muscle  internally  and  the  Occipito-frontalis  and  Sterno-mastoid  muscles  ex- 
ternally. 

4.  The  highest  curved  lixe  (linea  suprema)  is  above  the  superior  curved 
line  and  gives  attachment  to  epicranial  aponeurosis. 

5.  The  inferior  curved  lixe,  which  passes  outward  from  the  middle  of 
the  external  occipital  crest  together  with  a  depression  below  it.  gives  attach- 
ment to  the  Rectus  capitis  posticus  major  and  Rectus  capitis  posticus  minor. 

6.  The  depression  between  the  superior  and  inferior  curved  lines  gives 
attachment  to  the  Complexus  muscle  internally.  Splenitis  capitis  and  Superior 
oblique  externally. 

7.  The  foramen  magnum  is  a  large  oval  opening  near  the  inferior  angle. 
Its  greatest  diameter  is  antero-posteriorly.  It  transmits  the  following  struc- 
tures: (a)  the  medulla  and  its  membranes,  (b)  the  spinal  accessory  nerve,  (c) 
the  occipi to-axial  ligaments,  (d)  vertebral  arteries,  (e)  anterior  and  posterior 
spinal  arteries. 

8.  The  condyles  are  situated  on  each  side  of  the  anterior  pail  of  the 
foramen  magnum.  They  are  convex  and  reniform  in  shape.  They  look  back- 
ward and  outward  to  articulate  with  the  atlas. 

9.  The  tubercles  are  situated  on  the  inner  border  of  each  condyle  and 
give  attachment  to  the  check  ligaments. 

10.  The  jugulab  processes  (transverse)  are  situated  externally  to  the 
condyles,  and  help  to  form  the  posterior  lacerated  foramen. 

1 1 .  The  jugular  foramen  is  on  the  anterior  border  of  i  lie  jugular  process. 

12.  A  quadrilateral  facet  is  on  the  externa]  surface  of  the  jugular  pro- 
cess for  its  articulation  with  the  petrous  portion  of  the  temporal  bone. 

13.  A  deep  <;k<><>\  e  is  on  the  upper  surface  of  the  jugular  process  for  the 
lateral  sinus. 

14.  Ax  eminence  (paramastoid  in  animals),  which  may  extend  to  the 
transverse  process  of  the  atlas,  gives  attachmenl  to  the  Rectus  capitis  lateralis 
muscle  and  the  lateral  occipito-atlantal  ligament. 

1").  Anterior  condyloid  foramen  is  on  the  outer  side  of  each  condyle.    It 


5 1 2 


ANATOMY  IN  A  NTTSHELL. 


transmits  the  hypoglossal  nerve  and  some  meningeal  branches.  This  foramen 
may   lie  double. 

Hi.  Posterior  condyloid  foramen,  which  is  behind  the  condyle,  trans- 
mit.- a  vein  in  the  lateral  sinus.  It  is  at  the  bottom  of  the  posterior  condyloid 
fossa  and  is  often  absenl . 

The  basilar  process  of  the  occipital  hone  is  situated  anterior  to  the  foramen 
magnum  and  is  quadrilateral  in  shape.  The  pharyngeal  spine  (sagittal  ridge) 
is  on  its  under  surface  and  uives  attachment  to  the  tendinous  raphe  and  the 
Superior  constrictor  muscle.      There  is  a  depression  on  each  side  of  this  spine 

PLATE  CCLXVIII. 


SUB-PUOIC  LIGAMENT  WITH  APERTURE  FOR  DORSAL  VEIN  OF  THE  PENIS 
APERTURES  FOR  DORSAL  ARTERY  AND  NERVE  OF  PENIS 


APERTURE  FOR  AhTERY  OF  CORPUS  CAVERNOSUM 
CRUS  PENIS 


SUPERFICIAL  TRIANGULAR  LIGAMENT 
ISCHIO-CAVERNOSUS.  OR  ERECTOR  PENIS. 


APERTURE  FOR  ARTERY  TO  BULB 
URETHRAL  APERTURE 


APERTURE  FOR  COWPER  S   DUCT 
POSITION  OF  BULB 


APERTURES  FOR   SUPERFICIAL 
PERINAEAL  VESSELS  AND  NERVE 


DORSAL  NERVE 

ANTERIOR  LAYER  OF  TRIANGULAR 
LIGAMENT 

DORSAL  ARTERY  OF  PENIS 

'ERY  OF  CORPUS  CAVERNOSUM 

DEEP  TRIANGULAR  LIGAMENT 

ARTERY  TO  BULB 

PUDIC  VEINS 
DORSAL  NERVE. 
POSITION  OF  COWPER  S 
GLAND 
INTERNAL  PUDIC  ARTERY 


FASCIA  OF  COLLES 
TURNED  BACKWARDS 


POSTERIOR  BORDER  OF  PERINEAL  LEDGE 
JUNCTION  OF  TRIANGULAR  LIGAMENTS  WITH  FASCIA  OF  COLLES. 

Colles'  Fascia  \.nd  the  Triangular  Ligaments  of  Perineum. 
for  the  attachmenl  of  the  Rectus  capitis  anticus  major  ami  Rectus  capitis  anti- 
CUS  minor. 

The  Internal  or  cerebral  surface  of  the  occipital  hone  is  deeply  concave  ami 
has  the  following  points  for  consideration: 

1.  I'm  i;  FOSSAE  ate  foimed  by  a  crucial  ridge.  The  inferior  of  these  fossa' 
;iic  for  tie'  cerebellum  and  the  superior  ones  are  for  the  cerebrum. 

2.  Till.  INTERNAL  OCCIPITAL  PROTUBERANCE  lies  at  the  junction  of  the 
divisions  of  the  ridges.  It  is  the  point  where  the  six  cranial  sinuses  meet  to 
form  the  torcular  Herophili. 

'■'•.  Crucial  ridge  has  a  vertical  portion  which  is  for  the  falx  cerebri  (above) 
and  the  falx  cerebelli  (below);  and  a  transverse  portion  for  the  tentorium  cere- 

l.elli. 

4.  (d;<)<)\  ES  ai'c  presenl  between  the  attachment  of  the  dura  mater  for  the 
sinuses. 


ANATOMY    IN    A    NUTSHELL.  513 

5.  The  internal  openings  for  the  anterior  condyloid  foramina  and  pos- 
terior condyloid  foramina  are  seen  on  each  side  of  the  foramen  magnum. 

The  basilar  process  of  the  occipital  hone  on  its  inner  surface  has  a  median 
groove  for  the  medulla  and  the  pons,  and  on  each  side  of  this  groove  there  is  a 
narrow  groove  which  joins  another  groove  from  the  petrous  portion  of  the 
temporal  bone  to  receive  the  inferior  petrosal  sinus. 

The  superior  ancle  is  a  point  where  the  occipital  hone  meet-  the  two 
parietal  bones.     This  is  the  position  of  the  posterior  fontanelle. 

Each  lateral  angle  is  the  point  where  the  occipital  hone  meets  the 
posterior  inferior  angle  of  the  parietal  bone  and  the  mastoid  pail  of  the  tem- 
poral bone. 

The  inferior  angle  (basilar  process)  joins  the  body  of  the  sphenoid  hone. 

The  superior  border  passes  from  one  lateral  angle  to  the  superior  angle 
and  helps  to  form  the  lambdoid  suture. 

The  inferior  border  passes  from  the  lateral  angle  to  the  inferior  angle. 
The  upper  part  of  this  border  joins  the  mastoid  bone  and  the  lower  part  joins 
the  petrous  portion  of  the  temporal  bone. 


LESSON  CLXXII. 

Ossification. — It  has  from  four  to  eleven  centers  of  ossification. 

Articulation. — It  articulates  with  the  two  parietal,  two  temporal,  sphe- 
noid, and  atlas,  thus  making  six  bones. 

Attachment  of  Muscles. — It  has  twelve  pairs  of  muscles  attached  to  it, 
(1)  those  to  the  superior  curved  line  are  Occipitofrontal  is  of  the  frontal 
region,  Trapezius  of  the  first  layer  of  the  back,  and  Stemo-cleido-mastoid  of  the 
superficial  cervical  region. 

2.  To  the  space  between  the  curved  lines  are  the  Complexus  of  the 
fourth  layer  of  the  back,  Splenius  capitis  of  the  third  layer  of  the  hack,  and 
Superior  oblique  of  the  fifth  layer  of  the  back. 

3.  Those  attached  to  the  lnferiok  curved  line  and  the  space  re- 
twekn  it  and  the  foramen  macnum  are  the  Rectus  capitis  posticus  major, 
and  Rectus  capitis  posticus  minor  of  the  fifth  layer  of  the  back. 

4.  That  attached  to  the  transverse  process  is  the  Rectus  capitis 
lateralis  of  the  anterior  vertebral  region. 

5.  Those  attached  to  the  basilar  process  are  the  Rectus  capitis  anticus 
major,  and  Rectus  capitis  anticus  minor  of  the  anterior  vertebral  region,  and 
the  Superior  constrictor  of  the  pharynx  of  the  pharyngeal  region. 

Blood  Supply.— Occipital,  posterior  auricular,  middle  meningeal,  verte- 
bral, and  ascending  pharyngeal   arteries. 

Occipito-frontalis.  Description.— This  muscle  consists  of  an  anterior 
portion  called  frontal,  and  a  posterior  portion  called  occipital,  ami  a  third  por- 
tion  which   is  between   these  two   which   is  called   the  tendinous  aponeurosis. 

Origin.  The  occipital  portion  arises  from  the  outer  two-thirds  or  one- 
half  of  the  superior  curved  line  of  th 'cipital  hone  ami  the  mastoid  process  of 

the    temporal    hone.      The    frontal    portion    arises    from    the    I  'yramidalis    nasi. 


5]  i  AXATOMY  IX  A  NUTSHELL. 

Corrugator  supercilii,  and  Orbicularis  palpebrarum  muscles.  A  few  fibers  of  this 
muscle  may  be  attached  to  the  nasal  hone  and  the  frontal  bone. 

Ixsi  i;  i  [ON.      Into  the  tendinous  aponeurosis  of  the  vertex  of  the  skull. 

ACTION.— The  frontal  portion  draws  the  scalp  forward  and  raises  the  eye 
brows  and  skin  over  the  root  of  the  nose.  The  occipital  portion  draws  the  scalp 
backward.     The   Occipito-frontalis    muscle    is   chiefly   a    muscle   of    facial   ex- 

-!OH. 

\  i  i;\  i;  Supply.—  The  frontal  portion  receives  the  facial  nerve  or  branches 
of  the  third  nerve  which  join  this  nerve.  The  occipital  portion  receives  the  pos- 
terior auricular  branch  of  the  facial  and  sometimes  the  occipitalis  minor. 

Blood  Supply.  -The  frontal  portion  receives  the  supraorbital,  frontal, 
and  anterior  temporal  arteries.  The  occipital  portion  receives  the  occipital 
and  posterior  auricular  arteries. 

Trapezius  muscle.     For  description  of  this  muscle  see  page  4."). 

Sterno-cleido-mastoid.     For  description  of  this  muscle  see  page  40. 

Complexus.      For  description  of  this  muscle  see  page  27."). 

Splenius  capitis.      For  description  of  this  muscle  see  page  272. 

Superior  oblique.      For  description  of  this  muscle  see  page  278. 

Rectus  capitis  posticus  major.      For  description  of  this  muscle  see  page  278. 

Rectus  capitis  posticus  minor.      For  description  of  this  muscle  see  page  278. 

Rectus  capitis  lateralis. — Description. — This  muscle  belongs  to  the  an- 
terior   vertebral    region. 

Origin.— From  the  upper  surface  of  the  transverse  process  of  the  atlas. 

Insertion. — Into  the  under  surface  of  the  jugular  process  of  the  occipital 
bone. 

A<tio\. — To  draw  the  head  laterally. 

\i.i;\  i  Si  pply.     First  cervical  nerve  and  a  loop  between  it  and  the  second. 

Blood  Supply.     Prevertebral  branches  of  ascending  pharyngeal  artery. 

Rectus  capitis  anticus  major. —  DESCRIPTION. — This  muscle  belongs  to  the 
anterior  vertebral  region,  and  looks  as  though  it  were  a  continuation  upward 
of  the  Scalenus  anticus.      It  is  narrow  below  hut  broad  and  thin  above.  Be- 

hind it  are  the  Longus  colli  and  Rectus  capitis  anticus  minor  muscles.  In  front 
of  it  is  the  sympal hei ic  nerve. 

Origin.— From  the  anterior  tubercles  of  the  transverse  processes  of  the 
third,  fourth,  fifth,  and  sixth  cervical  vertebrae.  As  it  passes  upward  it  con- 
verges towards  ii>  fellow. 

INSERTION.      Into  the  basilar  process  of  the  occipital  bone. 

ACTION.  To  flex  and  rotate  the  head,  and  to  restore  it  to  its  natural  posi- 
tion after  being  drawn  backward. 

Nerve  Si  pply.  Firsl  cervical  and  a  loop  between  it  and  the  second  cer- 
vical nerve. 

Blood  Supply.     Prevertebral  branches  of  ascending  pharyngeal. 

Rectus  capitis  anticus  minor.  DESCRIPTION. — This  muscle,  which  is  short, 
lies  immediately  behind  the  Rectus  capitis  anticus  major  and  in  front  of  the 
occipito-atlantal  articulation.      Its  course  is  obliquely  upward  and  inward. 


ANATOMY    IN    A    NUTSHELL. 


.")  1  5 


Origin. — From  the  anterior  surface  of  the  lateral  mass  of  the  at  la-,  and 
from  the  root  of  Its  transverse  process. 

Insertion. — Into  the  basilar  process  immediately  behind  the  Rectus  cap*- 
it  is  anticus  major. 

Action. — Same  as  the  Rectus  capitis  anticus  major. 

Nerve  Supply.— Same  as  Rectus  capitis  amicus  major. 

Blood  Supply. — Prevertebral  branches  of  the  ascending  pharyngeal. 

Superior  constrictor. — Description. — This  muscle,  which  is  situated  at 
the  upper  part  of  the  pharynx.  i>  of  a  quadrilateral  shape  ami  thinner  ami  paler 

PLATE  CCLXIX. 


CRANSVERSALIS  FASCIA 


ILIAC  FASCIA 


PELVIU     PERITONEUM 


EXTRA- PERITONEAL   TISSUE 


RECTOVESICAL  FASCIA 


ABDOMINAL  MUSCLES 


ILIAC  CREST 


BORDER  OF  ACETABULUM 


■■•-  'I  -  '.£ 


ISCHIORECTAL  FASCIA 
SPHINCTERAL 


~.        "     &    :\A  'ikr^T>      APEX     OF      ISCHIORECTAL  FOSSA 
hf^  'J'  i,  ="",y, 

HI .    m0 


GLUTEUS  MAXIMUS 


OBTURATOR  FASCIA 

OBTURATOR  INTERN 
ALCOCK'S  CANAL  WITH  PUDIC  VESSELS 

The  White  Link  and  [schio-Rectal  Fossa. 

than  the  other  Constrictor  muscles.  Its  superior  fibers  pa--  beneath  the  Leva- 
tor palati  muscle  ami  the  Eustachian  tube.  Between  the  upper  border  of  this 
JBouscle  ami  the  basilar  process  this  muscle  is  deficient  in  fibers  ami  closed  by 
the  pharyngeal  aponeurosis.  This  interval  is  known  as  the  sinus  of  Morgagni. 
Origin. — (1)  From  the  lower  one-third  of  the  posterior  margin  of  the 
internal  pterygoid  plate,  (2)  its  hamular  process,  ■'■'<>  the  contiguous  portion  of 
the  palate  bone.  (4i  the  reflected  tendon  of  the  Tensor  palati  muscle, 
the  pterygo-maxillary  ligament,  (6)  the  aveolar  process  above  the  posterior 
extremity  of  the  mylo-hyoid  ridge,  i?i  a  few  fiber-  from  the  side  of  the  tongue. 


.510  ANATOMY    IN    A    NUTSHELL. 

Insertion. — Into  the  median  raphe  of  the  pharynx  and  to  the  pharyngeal 
spine  of  the  basilar  process  of  the  occipital  bone  by  fibrous  aponeurosis. 

Action. — To  constrict  the  pharynx. 

Nerve  Supply. — Branches  from  the  pharyngeal  plexus. 

Blood  Supply. — It  receives  its  blood  supply  from  the  blood  supply  to 
the  pharynx  which  is  (1)  superior  thyroid,  (2)  ascending  pharyngeal  from  the 
external  carotid,  and  (3)  the  pterygo-palatine  and  (4)  descending  palatine  from 
the  internal  maxillary. 


LESSON  CLXXIII. 
Temporal  Bone.     (Plates  CCLXVI-CCLXVII-CCLXVIII-CCLXIX.) 

The  temporal  bone  lies  at  the  inferior  lateral  portion  of  the  skull  and  con- 
sists of  a  squamous,  mastoid,  and  petrous  portion.  It  contains  the  organs  of 
hearing. 

The  squamous  portion  (scale-like)  forms  the  anterior  superior  part  of  the 
hone. 

The  external  surface  of  the  squamous  portion  is  convex  and  has  grooves 
on  its  posterior  part  for  the  deep  temporal  arteries.  It  has  attached  to  it  the 
Temporal  muscle,  and  forms  part  of  the  temporal  fossa.  A  part  of  the  tem- 
poral ridge  is  situated  between  this  portion  of  the  bone  and  the  mastoid  portion. 

The  zygomatic  process  arises  by  three  roots  and  extends  forward  to  artic- 
ulate with  the  malar  bone.  Its  anterior  root,  which  runs  inward  and  ends  in 
the  eminentia  articularis,  is  short  and  broad.  Its  middle  root,  also  called  post* 
glenoid  process,  passes  between  the  auditory  process  and  the  mandibular  por- 
tion of  the  glenoid  fossa.  The  posterior  root  passes  upward  and  backward 
from  the  upper  border  of  the  zygoma  and  forms  part  of  the  temporal  ridge  (here 
called  supramastoid  crest.) 

To  THE  (JPPEB  BORDER  of  the  ZYGOMA  is  attached  the  temporal  fascia. 
and  to  the  lower  border  and  concave  inner  surface  is  attached  the  Masseter 
muscle.  The  external  lateral  ligamenl  of  the  lower  jaw  is  attached  to  a  tubercle 
at  the  anterior  root  of  the  zygoma.  Between  the  anterior  and  middle  roots  of 
the  zygoma  is  the  glenoid  fossa,  the  anterior  or  mandibular  portion  of  which 
is  for  the  articulation  of  the  condyle  of  the  lower  jaw  and  is  covered  with  car- 
tilage, while  its  posterior  part  lodges  the  parotid  "land.  This  posterior  portion 
i-  formed  chiefly  by  the  tympanic  plate  which  forms  the  antero-inferior  wall  of 
the  externa]  auditory  meatus  and  ends  externally  in  the  auditory  process.  Tin-: 
Glaserian  fissure  divides  the  glenoid  fossa  and  transmits  the  tympanic 
branch  of  the  internal  maxillary  artery  and  lodges  the  processus  gracilis  malleus. 
The  opening  of  the  canal  of  Eugieb  is  situated  in  the  angle  between  the 
squamous  portion  and  petrous  portion  of  the  temporal  bone.  It  transmits 
the  chorda   tympana  nerve. 

The  internal  surface  of  the  squamous  portion  is  concave  and  has  eminences 
and  depressions  for  the  cerebral  convolutions,  also  grooves  for  the  middle 
meningeal  artery. 


ANATOMY    IX    A    NUTSHELL.  oil 

The  superior  bordeb  of  the  squamous  portion  is  thin  and  overlaps  the 
parietal  bone. 

The  antebo-infebiob  border  is  thick  and  articulates  with  the  greater  wing 
of  the  sphenoid  bone. 

The  mastoid  portion  of  the  temporal  bone  projects  like  a  nipple  from  the 
inferior  portion  of  the  bone  posteriorly. 

The  outer  surface  of  the  mastoid  process  has  attached  to  it  the  Occipito- 
frontalis  muscle  near  the  Retrahens  aurem.  The  mastoid  foramen  may  be  on 
this  part  of  the  bone  but  is  often  on  the  occipital  bone.  It  transmits  a  vein  to 
the  lateral  sinus  and  a  meningeal  branch  of  the  occipital  artery.  There  are 
numerous  small  foramina  on  this  surface. 

The  inner  surface  of  the  mastoid  process  has  a  deep  curved  fossa  for  the 
lateral  sinus.  This  process  gives  attachment  to  the  following  muscles.  (1) 
Sterno-cleido-mastoid.  (2)  Splenitis  capitis.  (3)  Trachelo-mastoid,  (4)  Digastric, 
(5)  Retrahens  aurem,  (6)  Occipito -frontalis. 

The  digastric  fossa  is  on  the  inner  side  of  the  mastoid  process.  The  occipital 
groove,  which  is  for  the  occipital  artery,  lies  parallel  to  the  digastric  fossa  in- 
ternally to  it.  The  mastoid  cells  are  situated  in  the  mastoid  process  and  open 
into  the  tympanum.  They  are  lined  with  mucous  membrane.  The  upper  ones 
are  large,  while  the  lower  ones  are  small. 

The  superior  border  of  the  mastoid  portion  articulates  with  the  pos- 
terior angle  of  the  parietal. 

The  posterior  border  articulates  with  the  occipital  bone  between  it- 
jugular  process  and  lateral  angle. 

The  petrous  portion  of  the  temporal  bone  is  of  a  pyramidal  form  and  i- 
situated  between  the  sphenoid  bone  and  the  occipital  bone.  This  portion  of 
the  bone  is  very  dense  and  hard.  It  contains  the  internal  and  middle  ear  and 
passes  forward  and  inward.  It  has  a  base,  an  apex,  three  surface.-,  and  three 
borders. 

The  base  is  situated  against  the  squamous  and  mastoid  portions,  the  lower 
half  of  this  base  can  be  seen  between  the  divergence  of  the  squamous  and  mas- 
toid portions,  but  the  upper  half  is  concealed  by  them.  The  base  presents  the 
following  points: 

The  meatus  auditobius  extebnus,  which  is  the  external  opening  of  the 
ear.  This  opening  lies  in  front  of  the  mastoid  process  between  the  posterior 
root  and  middle  root  of  the  zygoma.  The  upper  margin  of  this  opening  is 
smooth  and  belongs  to  the  squamous  portion  of  the  temporal  bone.  but  the  rest 
of  it  belongs  to  the  petrous  portion  of  the  temporal  bone  and  forms  the  second 
point  for  consideration  at  the  base  of  the  petrous  portion,  namely,  the  m  di- 
TORY  process  which  is  for  the  attachment  of  the  cartilage  of  the  ear. 

The  apex,  which  lies  internally  at  the  base  of  the  skull,  is  received  betw< 
the  greater  wing  of  the  sphenoid  and  the  basilar  process  of  the  occipital  bone. 
thus  forming  the  outer  boundary  of  foramen  lacerum  medium, and  contain-  the 
internal  carotid  canal. 

The  anterior  surface  of  the  petrous  portion  of  the  temporal  bone  form-  the 
back  part  of  the  middle  fossa  of  the  skull  and  i>  united  with  the  squamous 


.18 


ANATOMY    IN    A    NUTSHELL. 


portion  by  the  temporal  or  petro-squamous  suture.     It  has  six  points  for  con- 
sideration.    (Plate  CCXLVII.) 

1.  Opening  of  the  carotid  can  \i.,  which  is  for  tin1  interna]  carotid  artery 
and  plexus,  is  situated  near  the  apex. 

2.  A  depression  for  the  ( I:iss< ■'  i:t n  ganglion  of  the  fifth  nerve  above  the 
carotid  canal. 

o.  Hiatus  Fallopi]  is  ;i  groove  which  runs  outward  ami  backward.     This 
i-  for  the  »rcai  petrosal  nerve  and  branches  of  the  middle  meningeal  artery. 
4.  Foramen  for  the  small  petrosal  nerve. 

PLATE  CCLXX. 


••4 . 

IANGULAR         4.IGAMEN. 
•  .  PERIGNEAL  VESS. 


TUBEROSITY  OF  ISCHIUM 
NFERIOR   /HEMORRHOIDAL    VESS 


GREAT  SACRO-SCIATIC  LIGAMENT. 


INFERIOR  PUDENTAL  NERVE 
SUPERFICIAL  PERINEAL  NERVE 

INFERIOR   HAEMORRHOIDAL  NERVE 

CUTANEOUS  BRANCH  OF  FOURTH  SACRAL 


SUPERFICIAL  TRANSVERS'JS  PERINAEI 


Showing  the  Muscles  of  the  Perineum. 


.■>.  Eminence  over  the  superior  semicircular  canal  which  is  near  the  center 
of  this  surface. 

<>.  A  depression  external  to  the  eminence  over  the  tympanum. 

The  posterior  surface  of  the  petrous  portion  of  the  temporal  hone  forms  the 
anterior  pari  of  the  posterior  fossa  of  the  base  of  ihe  skull  and  has  the  following 
points  for  consideration:     (Plate  CCXLVII.) 

1.  Meatus  ^UDITORIUS  [NTERNUS,  which  is  a  short  canal  at  the  end  of 
which  is  the  lamina  cribrosa.  This  lamina  is  perforated  by  branches  of  the 
seventh  and  eighth  nerves,  which  puss  into  this  opening. 

2.  Opening  of  the   \<>i  eductus  vestibuli  which  is  behind  the  meatus 


ANATOMY    IN    A    NUTSHELL.  519 

auditorius  interims.     It  transmits  a  small  artery  and  vein  and  Lodges  a  process 
of  the  dura   mater. 

3.  An  angulah  depression,  which  transmits  a  vein  to  the  cancellous 
tissue  ami  lodges  a  process  of  the  dura  mater,  is  between  and  above  these  other 
openings. 


LESSON   CLXXIV. 

The  inferior  surface  of  the  petrous  portion  of  the  temporal  hone  forms  pai  I 
of  the  hase  of  the  skull  and  from  its  apex  to  its  base  it  has  the  following  points 
for  consideration:     (Plate  CCXLIX.) 

1.  A  rough  quadrilateral  surface  for  the  origin  of  the  Levator  palati 
and  Tensor  tympani  muscles. 

2.  Opening  <>f  the  carotid  canal  which  ascends  vertically  into  the  hone 
and  then  turning  runs  horizontally  forward  and  inward.  It  transmits  the 
interna]  carotid  artery  and  carotid  plexus. 

3.  Aqueductus  cochleae,  which  transmits  an  artery  and  vein  to  and  from 
the  cochlea. 

4.  Jugular  fossa  is  a  depression  for  the  sinus  of  the  internal  jugular  vein, 
and  with  the  occipital  hone  forms  the  foramen  lacerum  posterius,  which  trans- 
mits the  internal  jugular  vein  and  the  ninth,  tenth,  and  eleventh  cranial  nerves. 

5.  Foramen  foe  Jacobson's  nerve  (tympanic  branch  of  the  glossopharyn- 
geal) is  in  the  ridge  between  the  jugular  fossa  and  the  carotid  canal. 

6.  Foramen  for  Arnold's  nerve  (auricular  branch  of  the  pneumogastric) 
is  in  the  outer  wall  of  the  jugular  fossa. 

7.  The  jugular  surface  is  a  smooth  quadrilateral  facet  which  articulates 
with  the  jugular  process  of  the  occipital  bone. 

8.  Vaginal  process  ensheaths  the  rool  of  the  styloid  process  and  gives 
attachment  to  the  Tensor  palati  muscle. 

!).  Styloid  prockss,  which  is  about  an  inch  long  and  runs  downward,  for- 
ward, and  inward,  and  gives  attachment  to  the  stylo-hyoid,  stylo-maxillary 
ligaments,  and  to  the  Stylo-pharyngeus, Stylo-hyoid, and  Stylo-glossus  muscles. 

10.  STYLO-MASTOID  FORAMEN  is  between  the  styloid  process  and  the  mas- 
toid process.  It  is  the  end  of  the  aqueductus  Fallopii  and  transmits  the  facial 
nerve,  and  the  stylo-mastoid  artery  enters  it. 

11.  THE  AURICULAE   FISSURE,  which  is  between   the  auditory  and   mastoid 

processes,  is  for  the  exit   of  Arnold's  nerve. 

Till-:  SUPERIOR    BORDER  of   the  pet  nuts   portion   of  the  temporal   hone  i>   the 

longest  and  is  grooved  for  the  superior  longitudinal  sinus.  It  gives  attachment 
to  the  tentorium  cerebelli  and  has  a  notch  :it  its  inner  end  lor  the  fifth  nerve. 
It  separates  the  middle  fossa  of  the  base  of  the  skull   from   the  posterior  fossa. 

The  posterior  border  of  the  petrous  portion  of  the  temporal  bone  has  on 
its  inner  half  a  groove,  which  with  n  similar  groove  on  the  occipital  bone  l< 
ihe  inferior  petrosal  sinus.     On  the  outer  half  of  this  border  is  ;i  notch  which 
forms  part  of  the  jugular  foramen. 

Tut':  anterior  border  of  the  petrous  portion  of  the  temporal  bone  is  the 


520  ANATOMY    IN    A    NUTSHELL 

shortest  and  has  an  inner  portion  which  articulates  with  the  sphenoid  hone,  and 
an  outer  portion  which  joins  with  the  squamous  portion. 

The  processus  cochleariformis  is  a  thin  plate  of  hone  which  separates  two 
canals  at  the  petro-squamous  angle.  The  upper  of  these  canals  is  for  the 
Tensor  tynipani  muscle,  and  the  lower  one  for  the  Eustachian  tube.  They 
lead   into   the   middle  ear. 

Ossification. — This  hone  ossifies  from  ten  centers. 

ARTICULATION.  It  articulates  with  five  hones;  (1)  the  occipital.  (2)  parie- 
tal. (3)  sphenoid.  (4)  inferior  maxillary.  (5)  malar. 

Attachment  <>k  Muscles.— It  has  fifteen  muscles  attached  to  it: 

1.  T<>  the  SQI  VMOUS  PORTION  of  the  temporal  hone,  the  Temporal  muscle 
of  the  tempero-maxillary  region. 

2.  To  the  zygoma,  the  Masseter  muscle  of  the  temporo-maxillary  region. 

3.  To  Tin-:  mastoid  portion,  (a)  the  Occipito-frontalis  of  the  cranial  region, 
(b)  Sterno-cleido-mastoid  of  the  superficial  cervical  region,  (c)  Splenius  capitis 
of  the  third  layer  of  the  hack,  (d)  Traehelo-mastoid  of  the  fourth  layer  of  the 
hack.  ie)  Digastric  of  the  supra-hyoid  region,  (f)  Retrahens  aurem  of  the  auricu- 
lar region. 

4.  Tothe  styloid  process, (a)  Stylo-pharyngeus  of  the  pharyngeal  region. 
(b)  Stylo-hyoid  of  the  supra-hyoid  region,  (c)  Stylo-glosstts  of  the  lingual  region. 

.">.  To  the  petrous  portion, (a)  Levator palati of  the  soft  palate, (b)  Tensor 
tynipani  of  the  tympanic  region,  (c)  Stapedius  of  the  tympanic  region. 

I'.i. >  Supply. — The  stylo-mastoid  artery  from  the  posterior  auricular. 

It  enters  the  stylo-mastoid  foramen.  The  tympanic  artery  from  the  internal 
maxillary  .  It  passes  through  the  Glaserian  fissure.  Petrosal  artery  from 
the  middle  meningeal.  It  passes  by  the  hiatus  Fallopii.  Tympanic  from  the 
interna]  carotid  artery,  while  in  the  carotid  canal.  Auditory  from  the  basilar, 
which  enter-  the  internal  auditory  meatus  and  is  distributed  to  the  cochlea  and 
vestibule. 


LESSON  CLXXV. 
Origin  and  Insertion  <»f  the  Muscles  Attached  to  Temporal  Boxe. 

1.  Temporal  muscle  which  has  been  described  on  page  508. 

2.  Masseter  muscle.  -Description. — There  is  a  strong  layer  of  fascia 
which  is  derived  from  the  deep  cervical  fascia  which  covers  this  muscle  and  is 
connected  with  it.  This  fascia  i-  attached  to  the  lower  border  of  the  zygoma, 
and  posteriorly  it  covers  the  parotid  gland,  making  the  parotid  fascia.  The 
Masseter  muscle  consists  of  two  portions,  a  superficial  and  a  deep  portion.  The 
deep  portion  is  smaller  and  more  muscular  than  the  superficial  portion.  These 
two  portions  are  united  ;it  their  insertion.  The  parotid  gland  overlaps 
it-  posterior  margin,  while  it-  anterior  margin  overlaps  the  Buccinator  muscle. 
The  facial  vein  crosses  it-  lower  anterior  angle. 

Origin.  The  origin  of  the  superficial  portion  is  from  the  malar  process 
of  the  superior  maxillary  hone,  and  the  anterior  two-thirds  of  the  lower  border 
of  the  zygomatic  arch.     The  origin  of  the  deep  portion  is  from  the  posterior 


ANATOMY   IN   A    NUTSHELL. 


521 


one-third  of  the  lower  border  of  the  zygomatic  arch  and  all  of  its  inner  surface. 

Insertion. — The  insertion  of  the  superficial  portion  is  into  the  angle  and 
Lower  half  of  the  outer  surface  of  ramus  of  the  jaw.  The  insertion  of  the  deep 
portion  is  in  the  upper  half  of  the  ramus  and  outer  surface  of  the  coronoid  pro- 
cess of  the  lower  jaw. 

Action. — It  is  a  muscle  of  mastication.  It  raises  the  back  part  of  the 
lower  jaw. 

Nerve  Supply. — Masseteric  branch  of  inferior  maxillary  division  of  the 
fifth  nerve. 

Blood  Supply. — Facial  artery,  transverse  facial  artery,  and  the  masseteric 
branch  of  the  inferior  maxillary  artery. 

PLATECCLXXI. 


CAVITY  OF 
CERVIX  WITH 
AReOR  VITA 


EXTERNAL  CS 


The  Uterus,  Horizontal  Section. 


3.  Occipito-frontalis  muscle,  which  has  been  described  on  page  ">13. 

4.  Sterno-cleido-mastoid,  which  has  been  described  on  page  40. 

5.  Splenitis  capitis,  which  has  been  described  on  page  272. 

6.  Traehelo-masfoid,  which  lias  been  described  on  page  '-'7  1. 

7.  Digastric— Description.  This  muscle,  which  pierces  the  Stylo-hyoid 
muscle  near  its  insertion  on  the  hyoid  hone,  consists  of  two  fleshy  bellies  and  ;i 
rounded  tendon  between  them.  From  this  tendon  of  the  Digastric  a  broad 
aponeurosis  is  given  off  which  is  attached  to  the  body  and  greater  cornu  of  the 
hyoid  bone.     This  aponeurosis  is  called  the  supra-hyoid  aponeurosis. 


522  ANATOMY    IN    A    NUTSHELL. 

Origin. — The  origin  of  the  posterior  belly  is  from  the  digastric  groove  of 
the  mastoid  process  of  the  temporal  bone.  The  origin  of  the  anterior  holly  is 
from  the  fossa  on  the  inner  surface  of  the  inferior  maxillary  bone  near  the 
symphysis. 

Insertion.-  Into  its  central  tendon,  which  is  held  to  the  body  of  the  hyoid 
bone  by  the  supra-hyoid  aponeurosis. 

Action. — To  raise  the  hyoid  bone  and  tongue,  to  depress  the  lower  jaw 
and  assist  in  opening  the  mouth. 

Nerve  Supply. — The  posterior  belly  receives  the  facial  nerve,  while  the 
anterior  belly  receives  the  mylo-hyoid  branch  of  the  inferior  dental  nerve. 

Blood  Supply. — Facial  artery,  occipital  artery,  and  posterior  auricular 
artery. 

8.  Retrahens  aurem, — 

Origin.-    From  the  mastoid  process  of  the  temporal  hone. 

1  nsertk in.-     Into  concha  of  ear.  and  Lower  part  of  cranial  surface. 

Action.     To  km  rad  the  pinna. 

Nerve  Supply.— Posterior  auricular  branch  of  die  facial  nerve. 

Blood  Supply. —  Branches  from  posterior  auricular. 

9.  Stylo-pharyngeus. — Description. — This  muscle,  which  extends  from 
the  styloid  process  of  the  temporal  hone  to  die  pharynx,  is  a  long  slender  mus- 
cle, rounded  above  and  broad  and  thin  below.  The  stylo-pharyngeus  nerve  in 
passing  to  the  tongue  lies  on  die  outer  side  of  this  muscle. 

Origin.-   From  the  inner  side  and  base  of  styloid  process. 

Insertion.-  Into  the  Consl  ictor  muscles,  Palato-pharyngeus  muscle,  and 
the  posterior  border  of  die  thyroid  cartilage. 

Action.  -  To  elevate  and  widen  die  pharynx. 

Nerve  Si  pply.     Glosso-pharyngeal. 

Blood  Supply,  ts  same  as  die  blood  supply  to  die  pharynx,  which  is 
found  mi  page  315. 

K).  Stylo-hyoid. — Description.  — This  muscle  is  perforated  near  its  in- 
sertion by  the  tendon  of  die  Digastric  muscle.  It  is  situated  in  front  of  and 
above  die  posterior  belly  of  die  Digastric. 

Origin.-   From  the  styloid  process  of  the  temporal  hone  near  its  base. 

Insertion,     tnto  the  body  of  die  hyoid  b ■. 

Action.     Ii  elevates  and  retracts  the  hyoid  hone. 

Nerve  Supply.-  facial. 

Blood  Si  pply.     Same  a-  Digastric  muscle. 

11.  Stylo-glossus.  Im  -i  ription.-  This  is  the  shortesl  and  smallest  of  the 
Styloid  muscles. 

Origin,  from  the  anterior  and  external  surface  of  the  styloid  process 
near  its  apex,  and  from  the  stylo-hyoid  ligament  by  a  thin  aponeurosis. 

Insertion,  into  the  sides  of  the  tongue,  and  entering  the  dorsum  of  the 
tongue  blends  with  the  Lingualis  muscle  in  front  of  the  Hyo-glossus  muscle, 
and  its  oblique  portion  passes  over  the  Hyo-glossus  muscle  and  decussates  with 
its  fibers. 


ANATOMY    IX    A    NUTSHELL.  523 

Action. — To  elevate  and   retract    the   tongue. 

Nerve  Supply. — Hypoglossal. 

Blood  Supply. — Facial,  lingual  and  ascending  pharyngeal. 

12.  Levator  palati.— Description. — This  muscle,  which  is  long,  thick,  and 
rounded,  is  situated  on  the  outer  side  of  the  posterior  nares. 

Origin. — From  the  under  surface  of  the  apex  of  the  petrous  portioD  of  the 
temporal  bone,  and  from  the  inner  surface  of  the  cartilaginous  portion  of  the 
Eustachian  tube. 

[nsertiOn. — Into  the  posterior  surface  of  the  sofl  palate  where  ii  blends 
with   the  muscle  of  the  opposite  side. 

Action. — It  elevates  the  soft   palate. 

Nerve  Supply. — The  spinal  accessory  through  the  pharyngeal  plexus 
possibly  from  the  facial  through  the  petrosal  branch  of  the  vidian  nerve. 

Blood  Supply. — Ascending  palatine,  ascending  pharyngeal,  descending- 
palatine,  lingual. 

13.  Tensor  tympani. — Description. — This  muscle  is  situated  above  the 
osseous  portion  of  the  Eustachian  tube  in  a  bony  canal.  It  is  separated  from 
the  Eustachian  tube  by  the  processus  cochleariformis. 

Origin. — From  the  canal  it  is  situated  in.  under  surface  of  the  petrous 
portion  of  the  temporal  bone,  and  the  cartilaginous  portion  of  the  Eustachian 
tube. 

Ixskrtion. — Into  the  handle  of  the  malleus  near  its  root. 

Action. — To  tense  the  tympanic  membrane. 

Nerve  Supply. — From  the  otic  ganglion  of  the  fifth  nerve. 

Blood  Supply. — Tympanic  branch  of  ascending  pharyngeal. 

14.  Stapedius. — Description. — This  is  the  smallest    muscle  in   the  body. 
Origin. — From   the   sides   of   the  cavity   in   the    tympanum.      Its    tendon 

pusses  through  the  foramen  in  the  apex  of  the  pyramid. 

Insertion. — Into  the  neck  of  the  stapes. 

Action. — To  draw  the  head  of  the  stapes  backward  and  thus  rotating  it> 
base  inward  towards  the  vestibule,  and  probably  compressing  the  contents  of 
the  vestibule. 

Nerve  Supply. — Tympanic  branch  from  the  seventh. 

Blood  Supply. — Tympanic  branch  of  internal  maxillary. 

If).  Tensor  palati.-  Description.-  This  is  a  broad  triangular  muscle  with 
its  base  upward,  and  lies  at  the  outer  side  of  the  Levator  palati. 

Origin.—  From  scaphoid  fossa  :it  the  base  of  the  internal  pterygoid  plate, 
spine  of  sphenoid  bone,  vaginal  process  of  temporal  bone,  cartilaginous  portion 
of  the  Eustachian  tube,  and  hamular  process. 

Insertion.-    Into  the  anterior  surface  of  the  sofl   palate,  and  the  trans- 

verse  ridge  on  the  horizontal  portion  of  the  palate  bone. 

Action.— 11    tenses  the  soft    palate,  and  opens   Eustachian   tube  during 

deglutition. 

Nerve  Supply.     Otic  ganglion  of  the  fifth  nerve. 

Blood  Supply.  Ascending  palatine,  ascending  pharyngeal,  descending 
palatine,  lingual. 


524 


ANATOMY  IN  A   NUTSHELL. 


LESSON  CLXXVI. 
Ethmoid  Bone.     (Plates  CCLVIII-CCLIX. 
The  ethmoid  bone  which  consists  of  a  horizontal  plate  a  perpendicular  plate 
and  two  lateral  masses  is  situated  at  the  base  of  the  cranium  between  the  orbits. 
It  is  a  lighl  spongy  bone  and  cubical  in  form.     Its  body  has  the  following 
POI  NTS  FOR  <  onsideration: 

PLATE  CCLXXII. 


ca 


T0Rls  — 


A  Sagittal  Section  of  the  Female  Organs  of  Generation. 
1.  Cribriform  plate  (horizontal)  forms  pan  of  the  anterior  fossa  of  the 
skull  as  it  is  situated  in  the  ethmoidal  notch  of  the  frontal  bone  and  between 
it^  orbital  plates. 


ANATOMY    IN    A    NUTSHELL.  525 

2.  Crista  galli  is  situated  in  the  median  line  of  the  cribriform  plate  an- 
teriorly. It  is  thick  and  triangular.  The  long  border  of  this  triangle,  which 
is  the  posterior  one.  gives  attachment  to  the  falx  cerebri.     The  anterior  border 

of  this  triangle,  by  its  articulation  with  the  frontal  bone  completes  the  foramen 
caecum.     Between  the  two  laminae  of  this  triangle,  there  may  be  a  shuts. 

3.  Grooves  are  on  this  plate  on  each  side  of  the  crista  galli  for  the  olfactory 
bulbs. 

4.  Foramina  perforate  this  horizontal  plate  for  the  passage  of  the  olfactory 
nerves.  These  foramina  are  in  three  rows,  (a)  an  inner  row,  which  leads  to  the 
nasal  septum,  (b)  a  middle  row  which  leads  to  the  roof  of  the  nose,  and  (c)  an 
outer  row  which  leads  to  the  superior  turbinated    bone. 

5.  Nasal  slit  is  on  the  side  of  the  crista  galli  anteriorly  and  is  for  the 
passage  of  the  nasal  nerve,  which  is  a  branch  of  the  fifth  nerve. 

6.  Triangular  notch  is  at  the  back  of  the  cribriform  plate  for  the  ethmoid 
spine  of  the  sphenoid. 

7.  The  perpendicular  plate  descends  from  the  under  surface  of  the 
cribriform  plate  and  assists  to  form  the  nasal  septum.  Its  sides  are  grooved 
for  filaments  of  the  olfactory  nerves.  The  nasal  spine  of  the  frontal  and  crests 
of  the  nasal  bones  articulate  with  its  anterior  border.  The  ethmoidal  crest  of 
sphenoid  articulates  with  the  upper  half  of  its  posterior  border,  while  the  vomer 
articulates  with  the  lower  half  of  this  border.  The  triangular  cartilage  is  at- 
tached to  its  inferior  border. 

The  lateral  masses  of  the  ethmoid  bone  consist  of  a  number  of 
cellular  cavities,  and  each  lateral  half  presents  the  following  points 
for  consideration: 

1.  The  ethmoidal  cells  have  thin  walls  and  are  situated  between  two 
plates   which   form   its  sides. 

2.  Os  planum  or  orbital  plate  forms  the  outer  surface  of  these  cells  and 
also  forms  the  inner  wall  of  the  orbit.  It  articulates  with  the  orbital  plateof 
the  frontal  bone  above,  and  forms  the  anteriorand  posterior  ethmoidal  foramina 
by  their  notched  borders  coming  together  with  the  superior  maxillary  bone 
below,  with  the  Lachrymal  bone  in  front,  and  with  the  sphenoid  and  orbital 
process  of  the  palate  bone  behind. 

3.  The  middle  turbinated  process,  which  is  concave  outward  andforms 
part  of  the  middle  meatus,  is  the  end  of  a  thin  plate  of  bone  which  descends 
from  the  cribriform  plate,  and  forms  part  of  the  outer  wall  of  the  nasal  fossa. 

4.  The  superior  turbinated  process  curves  downward  and  outward. 

5.  The  UNCIFORM  PROCESS  passes  downward  to  articulate  with  the  in- 
ferior turbinated  bone  and  forms  part  of  the  inner  wall  of  the  antrum  of  High- 
more. 

OSSIFICATION.  It  ossifies  from  three  centers.  One  center  for  the  body 
and  one  for  each    lateral    mass. 

Articulation.  It  articulates  with  thirteen  bones,  namely,  the  sphenoid 
and  frontal  of  the  cranium,  and  all  the  bones  of  the  face  excepl  the  two  malar 

and  the  inferior  maxillary.     The  bones  of  the  face  it  articulates  with  are:  the 
two  nasal,  two  superior  maxillary,  two  lachrymal,  two  palate,  two  inferior  tur- 


526  ANATOMY  IX  A  NUTSHELL. 

binated,  and  the  vomer.  The  ethmoid  bone  with  its  articulations  form  the 
nasal  fossa.  The  two  sphenoidal  turbinated  bones  articulate  with  the  ethmoid 
also.  bu1  as  they  are  processes  of  the  sphenoid  we  do  not  name  them  in  the 
articulations  of  the  ethmoid,  since  the  sphenoid  itself  has  been  named. 

A  i  i  \<  hment  of  Muscles. — There  are  no  muscles  attached  to  this  hone. 

Blood  Supply.  Aaiterior  ethmoidal  artery,  posterior  ethmoidal  artery, 
ami  nasal  or  spheno-palatine  branch  of  internal  maxillary  artery. 

LESSON  CLXXVII. 
Sphenoid  Bone.     (Plates  CCXLIII-CCXLIV). 

'The  sphenoid  bone  forms  most  of  the  middle  fossa  at  the  base  of  the  skull. 
It  touches  all  the  hones  of  the  cranium,  the  vomer,  two  palate  and  two  malar 
0f  the  face.  Occasionally  its  external  pterygoid  plate  articulates  with  the 
superior  maxillary  hone.      It  presents  the  following  points  for  consideration: 

1.   A  body,  which  is  a  hollow  cuboid  structure  with  six  surfaces. 

The  superior  surface  has  in  front  THE  kthmoidal  SPINE  which  articulates 
with  the  cribriform  plate  of  the  ethmoid.  It  then  has  a  smooth  surface  with 
a  slight  longitudinal  eminence  in  the  mid-line  and  on  each  side  of  this  eminence 
is  a  groove  for  the  olfactory  tract.  The  next  point  is  the  optic  groove,  which 
lodges  the  optic  commissure  and  ends  on  each  side  in  thk  optic  FORAMEN  which 
is  for  the  passage  of  the  optic  nerve  and  the  ophthalmic  artery.  Thk  olivary 
process  is  immediately  behind  the  optic  groove.  Thk  sklla  Turcica  (pit- 
uitary fossa),  which  is  for  the  pituitary  body  (hypophysis)  of  the  brain,  is  just 
behind  the  olivary  process.  Thk  middle  clinoid  processes  bound  the  sella 
Turcica  in  front.  Thk  dorsum  skll.k  (dorsum  ephippii)  bounds  the  sella 
Turcica  behind,  and  is  grooved  on  each  side  for  the  sixth  nerve.  Thk  pos- 
terior clinoid  processes  are  a1  each  upper  angle  of  the  dorsum  sella?.  Grooves 
are  situated  laterally  on  the  body  for  the  cavernous  sinus  and  the  internal 
carotid  artery.  They  ate  curved  like  the  Italic  letter  f.  Thk  lingula  is  a 
ridge  along  the  outer  margin  of  this  groove  posteriori}-.  Thk  clivus  is  a  shallow 
depression  which  lodges  the  pons  and  slopes  backward  from  the  dorsum  sella' 
to  be  continuous  with  the  basilar  groove  of  the  occipital  bone. 

The  posterior  surface  joins  the  basilar  process  of  the  occipital  bone.     This 

ce  is  quadrilateral  in  shape  and  there  is  a  layer  of  cartilage  between  it  and 
the  occipital  bone  until  about  the  twentieth  year. 

The  anterior  surface  has  in  the  median  line  thk  ETHMOIDAL  CREST.  This 
cresl   articulates  with   the  perpendicular  plate  of  the  ethmoid.     Sphenoidal 

i  ELLS  or  sinuses  are  on  each  side  of  this  ethmoidal  crest.  Thk  SPHENOIDAL 
Ti  RBINATED  BONE  partly  closes  these  cells  or  sinuses  in  front  and  below,  but 
they  communicate  with  the  nose  and  sometimes  with  the  posterior  ethmoidal 
cell.-.  This  surface  articulates  with  the  orbital  process  of  the  frontal  bone 
above,  and  with  the  orbital  process  of  the  palate  bone  below,  and  with  the  os 

plannum    of    the    ethmoid    LATERALLY. 

The  inferior  surface  has  in  its  mid-line  Tin:  ROSTRUM,  which  articulates 
with  the  upper  edge  of  the  vomer.  Thk  vaginal  processes  are  on  each  side, 
and  articulate  with  the  alae  of  the  vomer.     This  inferior  surface  helps  to  form 


\  \  \TiiMV  IN  A   NUTSHELL. 


527 


the  nasal  fossa.  Grooves,  which  articulate  with  the  sphenoidal  processes  of 
the  palate  bone,  form  the  pterygo-palatine  canals  which  are  for  the  trans- 
mission of  the  pterygo-palatine  vessels  and  nerves. 

2.  The  greater  wings  of  the  sphenoid  arise  from  the  sides  of  the  body  and 
curve  upward,  outward,  and  backward.  Each  greal  wing  has  the  following 
points  for  consideration:  (a)  foramen  rotundum  for  the  superior  maxillary 
division  of  the  fifth  nerve,  (b)  foramen  ovale  or  the  inferior  maxillary 
division  of  the  fifth  nerve,  the  small  petrosal  nerve,  small  meningeal  artery, 
(c)  foramen  Vesalii  transmits  a  small  vein,  tins  foramen  is  often  absent,  (d) 
foramen  spinosum  transmits  the  noddle  meningeal  artery,  veins,  and  sympa- 
thetic filaments  from  the  cavernous  plexus.     This  foramen  is  often  double. 

PLATE  CCLXXIII. 


ANASTOMOSIS    OF    UTERINE    AND 
OVARIAN  ARTERIES. 


HELICINE     BRANCHES 
UTERO-OVARIAN     LIGAMENT 


FIMBRIATED     EXTRFMITY 
OF    TUBE 


MBRIA    OVARICA 
OVARIAN   ARTERY. 


ILIAC    INTERNAL 

VAGINAL     BRANCHES 
OS  EXTERNUM 


The  Uterus  With  Vagina  Laid  Open. 

The  external  surface  of  the  greater  wing  is  convex  and  is  divided  by  the 
transverse  pterygoid  ridge  into  an  upper  portion,  and  a  lower  portion.  The 
upper  portion  is  larger  and  forms  pari  of  the  temporal  fossa,  and  the  lower 
portion  forms  part  of  the  zygomatic  fossa.  This  lower  surface  ends  posteriorly 
in  the  spinous  process,  or  spine,  of  the  sphenoid.  This  process  gives  attach- 
ment  to  the  Tensor  palati  and  internal  lateral  ligament  of  the  lower  jaw. 

The  anterior  or  orbital  surface  of  the  greater  wing  of  the  sphenoid  forms 
pari  of  the  outer  wall  of  the  orbit,  and  is  quadrilateral  in  shape.  The  upper 
border  of  this  surface  articulates  with  the  frontal  bone,  the  outer  border  with 
the  malar  hone,  and  the  lower  border,  which  is  rounded,  helps  to  form  the 
pterygo-maxillary  fissure,  while  the  inner,  which  is  sharp,  forms  the  lower 
border  of  the  sphenoidal  fissure  (anterior  lacerated).     This  surface  has  a  notch 


528  ANATOMY  IN  A  NUTSHELL. 

at  its  upper  pari  for  a  branch  of  the  lachrymal  artery,  and  a  spine  at  its  center 
which  gives  origin  to  one  head  of  the  External  rectus  muscle. 

'I'lic  circumference  of  the  greater  wing  of  the  sphenoid  articulates  with 
the  temporal  and  frontal  hones.  Tart  of  its  inner  portion  forms  the  lower 
boundary  of  the  sphenoidal  fissure  and  helps  to  form  the  foramen  lacerum 
medium. 

3.  The  lesser  wings  ni  the  sphenoid  hone  (processes  of  Incrassias)  project 
outward  from  the  upper  and  lateral  part  of  the  body  to  end  in  a  sharp  point. 
Each  wing  has  two  roots;  the  upper  is  thin  and  flat,  and  the  lower  is  thicker  and 
has  near  the  body  a  small  tubercle  to  which  is  attached  the  ligament  of  Zinn. 
Tin;  OPTIC  FORAMEN  which  transmits  the  optic  nerve  and  the  ophthalmic  artery 
is  between  these  roots.  The  anterior  border  of  each  wing  articulates  with  the 
frontal  hone,  while  the  posterior  border  lies  in  the  fissure  of  Sylvius,  and  ends 
in  THE  INTERIOR  CLINOID  process  internally.  Its  upper  surface  is  smooth  and 
flat  and  is  situated  in  the  anterior  fossa  at  the  base  of  the  skull.  The  lower 
surface  forms  the  upper  border  of  the  sphenoidal  fissure  and  the  hack  of  the 
roof  of  the  orbit.  Tin-:  sphenoidal  fissure  (anterior  lacerated)  is  hounded 
above  by  the  lesser  wing  of  the  sphenoid,  internally  by  the  body  of  the  sphe- 
noid, and  below  by  the  inner  margin  of  the  orbital  surface  of  the  greater  wing 
of  the  sphenoid.  The  following  strictures  pass  through  the  sphenoidal 
fissure:  the  third  nerve,  fourth  nerve,  three  divisions  of  the  ophthalmic  division 
of  the  fifth  the  sixth  nerve,  filaments  from  the  cavernous  plexus  of  the  sympa- 
thetic, orbital  hranches  of  the  middle  meningeal  artery,  the  ophthalmic  vein, 
and  recurrent   branch  of  the  lachrymal  artery. 

4.  The  pterygoid  processes  of  the  sphenoid  bone  descend  on  either  side  from 
the  junction  of  the  body  witli  the  greater  wing.  Each  process  consists  of  two 
plates,  external  pterygoid  plate  and  internal  pterygoid  plate,  and  a  pterygoid 
fossa.  Tin:  external  pterygoid  plate  forms  part  of  the  inner  wall  of  the 
zygomatic  fossa  and  gives  attachment  to  the  External  pterygoid  muscle,  and 
its  inner  surface  gives  attachment  to  the  Internal  pterygoid  muscle.  Tin: 
internal  pterygoid  plate  is  longer  and  narrower  than  the  external  one  and 
has  on  its  extremity  the  hamular  process  around  which  the  tendon  of  the 
Tensor  palati  muscle  turns.  The  scaphoid  fossa  is  at  the  base  of  the  in- 
ternal pterygoid  plate  and  gives  origin  to  the  Tensor  palati  muscle.  The 
vidian  canal  is  at  the  loot  of  the  pterygoid  process  for  the  vidian  nerve  and 
vessels.  A  triangi  lap  notch  is  at  the  rool  of  the  hamular  process  to  articu- 
late with  the  pterygoid  process  of  the  palate  hone. 

5.  The  sphenoidal  turbinated  hones  (spongy)  articulate  in  front  with  the 
ethmoid  ami  with  the  palate  externally.  They  are  irregular  bones,  wide  an- 
teriorly, and  tapering  posteriorly. 

Ossifn  vtion.     This  bone  ossifies  from   fourteen   centers. 
Articulation.     It  articulates  with  twelve  hones  which  are.  the  two  malar, 

the  two  palate,  and  the  vomer  of  the  lace,  and  with  all  the  hones  of  the  cranium 
which  are.  frontal,  ethmoid,  two  parietal,  two  temporal,  and  the  occipital. 

Attachment  of  Mi  scles.  It  has  twelve  pairs  of  muscles  attached  to  it. 
TheTemporal  of  thetemporo-maxillary  region,  the  External  pterygoid  and  the 


ANATOMY    IX   A    NUTSHELL.  529 

Internal  pterygoid  of  the  pterygo-maxillary  region,  the  Superior  constrictor  of 
the  pharynx,  the  Tensor  palati  of  the  soft  palate  the  Levator  palpebral  of  the 

orbital  region,  the  Superior  oblique  of  the  orbital  region,  the  Superior  rectus. 
Inferior  rectus.  External  rectus,  and  Internal  rectus  of  the  orbital  region,  and 
the  Laxator  tympani. 

Blood  Supply. — Middle  and  small  meningeal,  anterior  deep  temporal, 
vidian,  pterygopalatine  and  spheno-palatine,  and  twigs  from  the  interna] 
carotid. 


LESSON  CLXXVIII. 

1.  Temporal  muscle  which  has  been  described  on  page  508. 

2.  External  pterygoid. — Description. — This  muscle,  which  passes  almost 
horizontally  between  the  zygomatic  fossa  and  the  condyle  of  the  jaw.  is  a  thick, 
short  muscle,  conical  in  form. 

Origin. — It  arises  by  two  heads  between  which  pass  the  buccal  nerve  and 
the  internal  maxillary  artery.  The  upper  head  comes  from  the  pterygoid  arch 
and  the  inferior  surface  of  the  greater  wing  of  the  sphenoid,  while  the  lower 
head  comes  from  the  outer  surface  of  the  external  pterygoid  plate,  and  from 
the  tuberosities  of  the  palate  and  superior  maxillary  bone. 

Insertion. — Into  a  depression  in  front  of  the  condyle  of  the  lower  jaw. 
and  the  inter-articular  fibro-cartilage. 

Action. — To  draw  the  condyle  and  interarticular  fibro-cartilage  forward 
and  inward. 

Nerve  Supply. — Pterygoid  branch  of  the  inferior  maxillary  division  of 
the  fifth. 

Blood  Supply. — External  pterygoid  branches  of  the  internal  maxillary 
artery. 

3.  Internal  pterygoid. — Description. — This  muscle  is  a  thick  and  quad- 
rilateral. 

Origin. — From  the  inner  surface  of  the  external  pterygoid  plate  and  from 
the  tuberosity  of  the  palate  bone,  and  the  adjacent  pari  of  the  superior  maxil- 
lary. 

Insertion.  —  Into  the  internal  surface  of  the  ramus  of  the  jaw  as  high  as 
the  mandibular  foramen  and  mylo-hyoid  groove. 

Action.— To  close  the  mouth  and  to  draw  the  lower  jaw  forward  and 
inward. 

Nerve  Supply. — Inferior  maxillary  division  of  the  fifth  nerve. 

Blood  Supply.  Branches  from  the  second  division  of  the  internal  maxil- 
lary artery. 

4.  Superior  constrictor  muscle  which  has  been  described  on  pa^ 

5.  Tensor  palati  muscle  which  ha-  been  described  on  page 

6.  Levator  palpebrae  (superioris).  Description.  This  muscle  is  tri- 
angular  in  shape  and  is  narrow  ami  tendinous  at  ii-  origin,  bu1  broad  and 
Meshy  in  its  center  and  ends  in  a  wide  aponeurosis  which  passes  between  the 
fibers  of  the  Orbicularis  to  it >  insertion. 

Origin. — From  the  under  surface  of  the  lesser  wing  of  the  sphenoid  bone 
above  and  in  front  of  the  optic  foramen. 


530  ANATOMY  IX  A  NUTSHELL 

[nsertion. — Into  the  aponeurosis  of  the  upper  t:\rsal  cartilage,  skin  of 
lid,  and  conjunctiva. 

Action. — Lifts  the  upper  lid  and  antagonizes  the  Orbicularis  palpebrarum. 

Nerve  Supply. — A  branch  of  the  third  nerve  which  pierces  the  su- 
perior rectus  muscle. 

Blood  Supply'. — Muscular  branches  from  the  ophthalmic  artery. 

7.  Superior  oblique.  -Description. — This  muscle  belongs  to  the  orbital 
region  and  receives  the  fourth  nerve. 

Orsgin. — From  above  the  inner  margin  of  optic  foramen.  Its  tendon 
passes  through  a  pulley  near  the  internal  angular  process  of  the  frontal  bone, 
then   beneath  the  Superior  rectus  muscle. 

Insertion.  Into  the  sclerotic  coat  between  the  Superior  rectus  and  Ex- 
ternal  rectus  muscle  at  right  angles  to  these  muscles. 

PLATE  CCLXXIV. 

SUPERFICIAL  DORSAL  VEIN 

DEEP  DORSAL  VEIN 

DORSAL  ARTERY 

CORPUS 
DARTOS  ■ 

AREOLAR  TISSUE 


ANTERIOR  BRANCH  - 
BULBO-CAVERNOUS  ARTERY 


CORPUS  SPONGIOSIS 


A  Transverse  Section  oe  the  Penis. 

Action. — it  rotates  the  eye-ball  on  its  antero-posterior  axis,  drawing  the 
cornea  downward  and  outward. 

Nerve  Supply*. — Fourth  cranial  nerve. 

Blood  Supply.     Muscular  branches  from  the  ophthalmic  artery. 

8.  Superior  rectus. —  Description. — This  is  the  thinnest  and  narrowest 
o  f  the  Recti  muscles. 

ORIGIN.  From  the  upper  margin  of  the  optic  foramen,  and  fibrous  sheath 
of  the  optic  nerve. 

Insertion.-  Into  the  sclerotic  coat  three  or  lour  lines  from  the  sclero- 
corneal  junction. 

Action.      Elevates  and  abducts  and  rotates  the  cornea  inward. 

Nerve  Supply. — Third  cranial  nerve. 

Blood  Si  pply. — Muscular  branches  of  the  ophthalmic  artery. 

U.    Inferior  rectus. 

Origin.     From  the  ligamenl  of  Zinn  with  the  Internal  rectus. 


ANATOMY     EN    A    NUTSHELL.  531 

Insertion. — Into  the  sclerotic  coat  three  of  tour  lines  from  the  sclero- 
corneal  junction. 

Action. — Abducts  the  cornea. 
Nerve  Supply. — Thin  I  nerve. 
Blood*Supply. — Muscular  branches  of  the  ophthalmic  artery. 

10.  External  rectus. — Description. — This  is  the  largesl  of  the  Recti 
muscles. 

Origin. — From  two  heads.  The  outer  head  from  the  outer  margin  of  the 
optic  foramen.  The  lower  head  from  the  ligament  of  Zinn  and  the  lower 
margin  of  the  sphenoidal  fissure. 

Insertion. — Into  the  sclerotic  coat. 

Action. — It  abducts  the  cornea. 

Nerve  Supply. — The  sixth  nerve. 

Blood  Supply. — Muscular  branches  from  the  ophthalmic  artery. 

All  the  structures  on  the  floor  of  the  sphenoidal  fissure  are  between  the 
two  heads  of  the  External  rectus  muscle,  namely,  ophthalmic  vein,  sixth.  two 
divisions  of  the  third,  and  the  nasal  branch  of  the  fifth  nerves. 

11.  Internal  rectus. — Description. — This  is  the  broadest  of  the  meet 
muscles. 

Origin. — From  the  ligament  of  Zinn. 

Insertion. — Into   the  sclerotic   coat. 

Action. — It  adducts  the  cornea. 

Nerve  Supply. — From  the  inferior  division  of  the  third  cranial  nerve. 

Blood  Supply. — Muscular  branches  of  the  ophthalmic  artery. 

12.  Laxator  tympani,  so-called  by  Sommeriny,  is  now  called  the  anterior 
ligament  of  the  malleus.  It  is  attached  tuthe  neck  of  the  malleus  and  to  the 
anterior  wall  of  the  tympanum,  with  some  of  its  fibers  passing  through  Glas- 
erian  fissure  to  the  spine  of  the  sphenoid  bone. 


LESSON  CLXXIX. 
Nasal  Bone.     (Plate  CCL). 

The  nasal  bone,  which  with  its  fellow  forms  the  bridge  of  the  nose,  is  a 
bone  with  two  surfaces  and  four  borders.  It  is  situated  at  the  upper  part  of 
the  face. 

The  outer  surface  is  convex  transversely,  but  concave  from  above  down- 
wark.  It  has  many  small  furrows  for  arteries,  and  at  its  center  a  foramen  for 
a   vein.     This  foramen   may   be  double. 

The  inner  surface  is  jus!  the  reverse  of  the  ohter  surface,  which  makes  it 
concave  transversely  and  convex  from  above  downward.  There  i-  a  longi- 
tudinal groove  on  this  surface  for  a  branch  of  the  nasal  nerve. 

The  superior  border  articulates  with  the  nasal  notch  of  the  frontal  bone. 
It  is  serrated,    thick,  ami    narrow. 

The  inferior  border  is  thinner  and  broader  than  the  superior  border,  ami 
gives  attachment  to  the  lateral  cartilage.  There  is  a  notch  at  its  middle  for 
the  branch  of  the  nasal  nerve. 

The  external  border  articulate-  with  the  nasal  process  of  the  superior 
maxillary  bone. 


ANATOMY    IN    A    NUTSHELL. 

The  internal  border  articulates  with  its  fellow,  and  with  the  nasal  spine  of 
the  frontal  bone  above  and  the  perpendicular  plate  of  the  ethmoid    below. 

Ossification. — It  ossifies  from  one  center. 

Articulation. — It  articulates  with  four  bones.  The  frontal  and  ethmoid 
of  the  cranium,  and  its  fellow  and  the  superior  maxillary  of  the  fare. 

An  \<  iiMi.vr  of  Muscles. — A  few  fibers  of  the  Occipito-frontalis  of  the 
cranial  region  may  he  attached  to  this  hone 

Blood  Supply.  Nasal  branch  of  the  ophthalmic  artery,  frontal,  the 
angular  and  the  anterior  tehmoidal  arteries. 

For  ORIGIN  and  ensertion  of  the  Occipito-frontalis  muscle  see  page 
Lachrymal  Bonk.     (Plate  CCLI.) 

The  lachrymal  bone  lies  on  the  anterior  part  of  the  inner  wall  of  the  orbit. 
It  resembles  a  finger  nail,  and  has  the  following  points  for  consideration: 

The  external  surface  has  upon  it  a  vertical  ridge  called  the  lachrymal 
cresl  which  passes  in  its  mid-line  and  ends  below  in  the  hamular  process.  This 
process  is  sometimes  separated  from  the  bone  and  then  is  called  the  lesser 
lachrymal  bone.  It  helps  to  form  the  lachrymal  groove  above  by  articula- 
ble with  the  lachrymal  tubercle  of  tin'  superior  maxillary  bone.  The  portion 
of  this  surface  behind  the  lachrymal  crest  helps  to  form  the  inner  wall  of  the 
orbit,  while  the  part  in  front  of  the  lachrymal  crest  forms  part  of  the  lachrymal 
groove. 

The  internal  surface,  or  nasal  surface,  forms  part  of  the  middle  meatus  by 
its  anterior  portion,  while  its  posterior  portion  by  its  articulation  with  the 
ethmoid  bone  completes  the  anterior  ethmoidal  canals.  This  surface  has  a 
furrow  upon  it  corresponding  to  the  position  of  the  crest  of  the  external  surface. 

The  anterior  border  articulates  with  tin1  nasal  process  of  the  superior 
maxillary  bone  and  is  the  longest. 

The  posterior  border  articulates  with  the  os  planum  of  the  ethmoid. 

The  superior  border,  which  is  the  shortest  and  thickest,  articulates  with 
the  internal  angular  process  of  the  frontal  bone. 

The  inferior  border  articulates  with  the  lachrymal  process  of  the  inferior 
turbinated  bone,  and  posteriorly  with  the  orbital  plate  of  the  superior   maxil- 
lary bone     These  two  portions  of  this  border  are  separated  by  thecrest. 

Ossification. — It  ossifies    from  one  center. 

Articulation.  It  articulates  with  four  bones.  The  frontal  and  ethmoid 
of  the  cranium,  and  the  superior  maxillary  and  inferior  turbinated  of  the  face. 

Attachment  of  Muscles.  —  It  has  one  muscle  attached  to  it.  namely,  the 
Tensor  tarsi  i  f  the  palpebral   region. 

Blood  Supplj  .  Inferior  orbital,  nasal  branch  of  ophthalmic,  and  anterior 
ethmoii  lal  artei  ies. 

Tensor  tarsi.  Descr iption.— This  muscle  is  the  deep  part  of  the  Orbi- 
cularis palpebral  urn. 

Origin. — It  arises  from  the  crest  of  the  lachrymal  bone  and  passes  across 
the  lachrymal  sac  and  divides  into  two  portions. 

Insertion.     Into  the  upper  and  lower  tarsal  cartilages. 


ANATOMY  IN  A  NUTSHELL. 


Action. — To  compress  the  puncta  lachrymals  againsl  the  globe  of  the 
eye,  and  to  compress  the  lachrymal  sac  into  a  position  mosl  favorable  for  re- 
ceiving the  tears. 

Nerve  Supply. — Facial,  and  perhaps  the  third  nerve. 

Blood  Supply. — Branches  from  the  facial  artery. 

PLATE  CCLXXV. 

ORIFICES  OF 
URETERS 

PLICA   URETERICA 
TRIGONE 
WTERNAL  URINARY  MEATUS 

PROSTATE  GLAND 
IFICES  Or  PROSTATIC  DUCTS 
SINUS  POCULARIS 

COWPEIVS  GLAND 
MEMBRANOUS  URETHRA 
CRUS   PENIS 


ORIFICE  OF  DUCT  OF 
COWPER'S  GLAND 

PECTINIFORM  SEPTUM 


RPUS  SPONGIOSUM 
PORA  CAVERNOSA 
rOSSA  NAVICULARS 
GCANS 
NAL  URINAY  MLATUS 


A  Horizontal  Section  op  the  Penis. 


LESSON  CLXXX. 
Malab  Bone.     (Plates  CCLIV-CCLT 
The  malar  bone,  or  check  bone,  is  situated  at  the  outerand  upper  part-  of 

the  face.     It  forms  part  of  the  outer  wall  and  the  floor  of  the  orbit,  and  part  of 
the  temporal  and  zygomatic  fossae. 


;,.U  ANATOMY  IN  A  NUTSHELL. 

The  external  surface  of  the  malar  hone  is  convex  and  gives  attachment 
to  the  Zygomaticus  major  and  the  Zygomaticus  minor.  It  has  a  malar  fora- 
men tor  malar  branch  of  temporo-malar  nerve  and  vessels. 

lt>  inner  surface  is  concave  and  has  a  triangular  rough  surface  for  its  artic- 
ulation with  the  superior  maxillary.  It  has  a  smooth  concave  surface  ex- 
ternally  which  forms  part  of  the  temporal  fossa  above  and  part  of  the  zygo- 
matic fossa  below.     This  surface  gives  origin  to  the  Masseter  muscle. 

The  orbital  border,  or  antero-superior,  forms  part  of  the  circumference  of 
the  oribt. 

The  maxillary  border,  or  antero-inferior,  articultaes  with  the  superior 
maxillary  hone.  The  Levator  labii  superioris  propius  muscle  is  attached  to 
this  border. 

The  temporal  border,  or  post  em-superior,  is  a  curved  border.  The  tem- 
poral fascia  is  attached  to  this  border  which  is  continuous  with  the  temporal 
ridge  above  and  with  the  upper  border  of  the  zygomatic  arch  below. 

The  zygomatic  border,  or  postero-inferior,  is  continuous  with  the  lower 
border  of  the  zygomatic  arch  and  gives  origin  to  the  Masseter  muscle. 

The  maxillary  process  articulates  with  the  superior  maxillary  bone.  It  is 
rough  ami  triangular. 

The  zygomatic  process  articulates  with  the  zygomatic  process  of  the  tem- 
poral  hone. 

The  frontal  process  articulates  with  the  external  angular  process  of  the 
frontal    hone. 

The  orbital  process  passes  backward  forming  part  of  the  floor  and  outer 
wall  of  the  orbit.  It  also  forms  part  of  the  temporal  fossa  and  bounds  the 
spheno-maxillary  fissure  anteriorly.  It  presents  the  inner  opening  of  the  tem- 
poro-malar canals. 

Ossification.—  From  two  or  three  centers. 

Articulation. — It  articulates  with  four  bones.  The  frontal,  sphenoid, 
and  temporal  of  the  cranium,  ami  the  superior  maxillary  of  the  face. 

An  \<  iimi.vi  of  Muscles.—  It  has  five  muscles  attached  to  it.  Levator 
labii  superioris  propius  of  the  superior  maxillary  region,  Zygomatic  major  and 
Zygomatic  minor  of  the  superior  maxillary  region,  the  Masseter  of  the  temporo- 
maxillary  region,  Temporal  of  the  temporo-maxillary  region. 

Blood  Supply.  Interim'  orbital,  lachrymal  branches  of  the  ophthalmic, 
transverse  facial,  and  deep  temporal  arteries. 

Levator  labii  superioris  proprius. — 

Origin.-  From  the  superior  maxillary  bone  above  the  infraorbital  foramen, 
al.-o  from  the  lower  border  of  the  maxillary  process  of  the  malar  bone. 

Insertion.     Into  the  facial  part  of  the  Orbicularis  oris. 

\>  i  [ON.      To  elevate  ami  protrude  the  lip. 

\'l.l;\  l.  Si   PPL1  .       facial   nerve. 

Blood  Supply.     Branchesfrom  the  facial  artery. 

The  infraorbital  plexus,  which  is  formed  by  the  fifth  and  seventh  nerves 
and  the  anastomosis  of  the  infraorbital  and  facial  arteries,  are  beneath  this 
muscle. 


ANATOMY  IN  A  NUTSHELL.  535 

Zygomaticus  major. — 

Origin. — From  the  malar  bone  on  its  posterior  asped  of  external  border. 

Insertion. — Into  the  angle  of  the  mouth. 

Action. — It  raises  the  lip  outward. 

Nerve  Supply. — Facial. 

Blood  Supply. — Branches  from  the  facial  artery. 

Zygomaticus  minor. — Stenson's  dud  the  facial  artery  and  vein  pass  under 
this  muscle. 

Origin. — From  the  anterior  aspect  of  the  external  surface  of  the  malar 
bone. 

Insertion. — Into  the  angle  of  the  mouth,  where  it  blends  with  the  Levator 
labii  superioris. 

Action. — To  raise  the  lip  outward. 

Nerve  Supply. — Facial. 

Blood  Supply. — Branches  from  the  facial  artery. 

Masseter  muscle  which  has  been  given  on  page  520. 

Temporal  muscle  which  has  been  given  on  page  508. 


LESSON  CLXXXI. 

Superior  Maxillary  Bone.     (Plates  CCLII-CCLIII). 

The  superior  maxillary  bones  are  two  in  number  and  form  the  upper  jaw. 
There  is  only  one  bone  of  the  face  larger  than  the  superior  maxillary  and  that 
is  the  inferior  maxillary.  This  bone  forms  parts  of  the  roof  of  the  mouth,  of 
the  floor  and  outer  wall  of  the  nose,  of  the  Moor  of  the  orbit;  and  parts  of  the 
zygomatic  and  spheno-maxillary fossae,  spheno-  and  pterygo-maxillary  fissures. 

The  body  of  the  superior  maxillary  bom1  is  a  hollow  cube.  This  hollow 
is  called  the  antrum  of  Highmore. 

The  external  surface,  or  facial  surface  of  the  body,  looks  forward  and  out- 
ward. On  this  surface  we  have  the  following  points  for  consideration:  The 
incisive  fossa  is  just  above  the  incisor  teeth  and  gives  origin  for  the  Depressor 
alse  nasi  muscle.  Just  below  this  fossa  a  portion  of  the  Orbicularis  oris  is  at- 
tached to  the  aveolar  border.  External  to  this  fossa  is  the  origin  of  the  Com- 
pressor alse  nasi.  The  canine  fossa,  which  skives  origin  to  the  Levator  anguli 
oris,  is  separated  from  the  incisive  fossa  by  the  canine  eminence.  Tins  emi- 
nence is  a  vertical  ridge  produced  by  the  canine  tooth.  The  infraorbital  fora- 
men, which  is  for  the  infraorbital  vessels  and  nerve,  is  above  the  canine  fossa. 
The  margin  of  the  orbit  gives  attachment  to  the  Levatorlabii  superioris  propus 
muscle. 

The  posterior,  or  zygomatic  surface  is  convex  and  forms  pari  of  the  zygo- 
matic fossa.  ()n  this  surface  we  have  the  following  points  for  consideration: 
Near  its  center  are  the  openings  of  the  posterior  dental  canals  for  the  posterior 
dental  vessels  ami  nerve.  The  tuberosity,  which  is  at  the  lower  pan  of  this 
surface,  gives  origin  to  the  Internal  pterygoid  muscle.  This  tuberosity  artic- 
ulates with  the  tuberosity  of  the  palate  bone  and  some  time-  with  the  external 
pterygoid  plate  of  the  sphenoid.     A  groove  just  above  this  tuberosity  i-  con- 


536 


ANATOMY    IX    A    XUTSHELL. 


verted  into  the  posterior  dental  canal  by  its  articulation  with  the  palate  bone. 
The  superior  surface,  or  orbital  surface,  forms  part  of  the  floor  of  the  orbit. 
Its  inner  border  articulates  with  the  orbital  process  of  the  palate  bone  behind, 
and  with  the  os  planum  of  the  ethmoid  in  the  middle,  and  with  the  lachrymal 
bone  in  front.  Its  outer  border  helps  in  form  the  spheno-maxillary  fissure 
and  sometimes  articulates  with  the  orbital  plate  of  the  sphenoid  bone.  Its 
anterior  border  helps  to  form  the  circumference  of  the  orbit  and  is  continuous 

PLATE  CCLXXVI. 


SPERMATIC  ARTERY 


PAMPINIFORM    PLEXUS 


HEAD    Of    EPIOIDYMUS 
GLOBUS     MAJOR  — 


HYATID    MORGAGNI 


ARTERY     OF 
VAS     DEFERENS. 


TAIL   OF    EPIDIOYMUS 
GLOBUS       MINOR  — 


PARIETAL     PORTION    OF     TUNICA    VAGINALIS.' 

Testicle  \\i>  Spermatic  Cord. 

with  the  nasal  process  internally  and  the  malar  process  externally.  The  in- 
fraorbital groove,  which  is  for  the  infraorbital  vessels  and  nerve,  runs  forward 
in  the  mid-line  to  end  in  the  infraorbital  canal  and  foramen.  This  canal  also 
opens  into  a  small  canal  which  runs  in  the  anterior  wall  of  the  antrum  for 
the  passage  of  the  anterior  dental  vessels  ami  nerve.  There  may  also  be  a  sec- 
ond dental  canal  for  the  middle  dental  nerve  which  passes  to  the  bicuspid  teeth. 
The  Inferior  oblique  muscle  of  the  orbital  region  arises  from  a  depression  just 
external    to    the    lachrymal    groove. 


ANATOMY    IX    A    NUTSHELL.  537 

The  internal  surface  is  divided  into  two  partsby  the  palate  process.  The 
part  above  the  palate  process  forms  part  of  the  outer  wall  of  the  nasal  fossa 
and  has  the  large  opening  of  the  antrum  of  Highmore.  The  part  below  the 
palate  process  forms  part  of  the  roof  of  the  mouth  and  is  concave.  Above  the 
opening  of  the  antrum  of  Highmore  are  half  cells  which  are  completed  by  artic- 
ulation with  the  ethmoid  and  lachrymal  hones,  while  below  the  opening  of  the 
antrum  of  Highmore  is  a  smooth  surface  which  forms  part  of  the  inferior  meatus. 
Behind  this  opening  is  a  rough  surface  which  articulates  with  the  perpendicular 
plate  of  the  ethmoid.  This  surface  is  crossed  obliquely  by  a  groove  which  is 
converted  into  the  posterior  palatine  canal  by  its  articulations  with  the  palate 
bone.  The  lachrymal  groove  is  in  front  of  the  antrum  of  Highmore  and  lodges 
the  lachrymal  duct.  It  is  converted  into  a  canal  by  its  articulation  with  the 
lachrymal  and  inferior  turbinated  hones.  The  inferior  turbinated  crest,  which 
articulates  with  the  inferior  turbinated  hone,  is  anterior  to  the  lachrymal 
groove.  The  middle  meatus  is  the  concavity  above  this  crest,  while  the  part 
below  it  is  the  inferior  meatus. 

The  antrum  of  Highmore  (maxillary  sinus)  (Plate  CCLXIV)  is  a  pyramidal 
cavity  in  the  body  of  the  superior  maxillary  bone.  The  apex  of  this  cavity  is 
formed  by  the  malar  process  and  its  walls  are  the  orbital,  facial,  and  zygomatic 
surfaces  of  the  body  of  the  sphenoid  bone.  The  outer  wall  of  the  nose  forms 
its  base  in  which  there  is  the  opening.  This  opening  is  partly  closed  by  the 
ethmoid  bone  above,  by  the  inferior  turbinated  below,  by  the  palate  bone 
behind.  The  posterior  dental  canals,  which  are  for  the  posterior  dental  vessels 
and  nerve,  are  on  the  posterior  wall  of  this  antrum.  Processeson  the  floor  of 
the  antrum  are  produced  by  first  and  second  molar  teeth. 

The  malar  process,  which  is  triangular  and  rough,  is  situated  between  the 
facial  surface  and  the  zygomatic  surface  and  articulates  with  the  malar  bone. 
This  process  gives  partial  origin  to  the  Masseter  muscle. 

The  nasal  process,  which  passes  upward,  inward  and  backward  by  the  side 
of  the  nose  is  triangular  and  thick.  The  Levator  labii  superioris  alaeque  nasi. 
Orbicularis  palpebrarum,  and  Tendo  oculiare  attached  to  its  external  surface. 
Its  interna]  surface  makes  part  of  the  outer  wall  of  the  nose.  The  upper  part 
of  this  surface  articulates  with  the  ethmoid  hone  completing  the  anterior 
ethmoidal  cells,  while  below  this  is  the  superior  turbinated  cresl  which  artic- 
ulates with  the  middle  turbinated  bone.  The  middle  meatus  is  immediately 
below,  and  below  the  middle   meatus  is  the  inferior  turbinated  crest. 

The  upper  border  of  the  nasal   process  articulates  with   the  frontal   bone. 

The  anterior  border  of  this  process  articulates  with  the  nasal  bone. 

The  posterior  border  of  this  process  has  the  lachrymal  groove  for  the  nasal 

duct,    and  the  inner  margin  of  this  groove  articulates  ith  the  lachrymal    bone. 

while  the  outer  margin  of  this  groove  forms  pari  of  the  circumference  of  the 

Orbit.      Where  it  joins  with  the  orbital  surface  is  the  lachrymal  tubercle. 

The  lachrymal  groove  is  made  into  a  canal  by  the  lachrymal  bone  and  the 
lachrymal  process  of  the  inferior  turbinated  bone.  This  canal  which  opens 
into  the  inferior  meatus,  runs  downward,  outward,  and  backward.  (Plate 
CCLII.) 


538  ANATOMY    IN    A    NUTSHELL. 

Areolar  process  lias  eighl  cavities  in  it  for  the  teeth.  This  process  is  broad- 
est behind  and  is  the  most  spongy  part  of  the  superior  maxillary  bone.  Its 
outer  surface  behind  the  first  molar  tooth  gives  origin  to  the  Buccinator  muscle. 

The  palate  process,  which  passes  inward  from  the  inner  surface  of  the 
body,  forms  part  of  the  floor  of  the  nasal  cavity  and  the  roof  of  the  mouth. 
On  its.  lnferior  surface  is  a  longitudinal  groove  or  canal  for  the  posterior 
palatine  vessels  and  the  anterior  and  external  palatine  nerves.  It  articulates 
with  the  vomer,  the  palate,  and  with  its  fellow  process  of  the  opposite  side. 
At  the  point  where  the  two  palate  processes  meet  anteriorly  is  the  anteriok 
palatine  canal  or  fossa.  There  are  four  openings  in  the  bottom  of  this 
fossa,  the  two  lateral  openings  are  called  foramina  of  Stenson,  and  transmit 
anterior  branches  of  the  descending  palatine  arteries.  The  anterior  and  pos- 
terior foramina  are  called  the  foramina  of  Scarpa,  and  transmit  the  naso-pala- 
tine  nerves.  The  left  nerve  passing  through  the  anterior  one  and  the  right 
nerve  through  the  posterior  one.  Sometimes  a  suture  passes  from  this  fossa  on 
each  side  to  the  interval  between  the  canine  and  incisor  teeth,  thus  making  a 
bone  called  the  intermaxillary  or  incisive  hone.  See  plate  CCXXVIII. 
The  SUPERIOR  SURFACE  is  concave  transversely  and  forms  part  of  the  floor  of 
the  nose,  and  has  the  upper  openings  of  the  canal  of  Scarpa  and  the  canal  of 
Stenson.  The  anterior  part  of  the  inner  border  of  this  surface  is  called  the 
nasal  crest,  which  articulates  with  its  fellow  thus  making  a  groove  to  receive 
the  vomer.  The  anterior  extremity  of  the  nasal  crest  is  the  anteriok  nasal 
SPINE. 

OSSIFICATION. — This    bone   ossifies    from    seven    centers. 

Articulation. — it  articulates  with  nine  bones.  The  frontal  and  ethmoid 
of  the  cranium,  and  the  nasal,  malar,  lachrymal,  inferior  turbinated,  palate, 
and  vomer  of  the  face,  and  with  its  fellow  of  the  opposite  side.  Sometimes 
it  articulates  with  the  external  pterygoid  plate  of  the  sphenoid  and  also  with 
the  orbital   plate  of  the  sphenoid. 

Attachment  of  Muscles. — It  has  twelve  muscles  attached  to  it.  The 
Orbicularis  palpebrarum  of  the  palpebral  region,  the  Inferior  oblique  of  the 
orbital  region,  Levator  labii  superioris  aleque  nasi  of  the  nasal  region,  Levator 
anguli  oris  of  the  superior  maxillary  region,  the  Compressor  nasi.  Depressor 
alse  nasi,  Dilator  nares  posterior  of  the  nasal  region,  Masseter  of  the  temporo- 
maxillary  region,  Buccinator  of  the  inter-maxillary  region.  Internal  ptery- 
goid of  the  pterygo-maxillary  region,  Orbicularis  oris  of  the  intermaxillary 
region,  Levator  labii  superioris  propius  of  the  superior  maxillary  region. 

lb. odd  Supply.  Infraorbital,  alveolar,  descending  palatine,  ethmoidal, 
frontal,    nasal,   and    facial    arteries. 


LESSON  CLXXXII. 

I  1  i  Orbicularis   palpebrarum   muscle   has   been    described   on  page  508. 

(2)    Inferior  oblique. 

Origin.     It  arises  fr the  orbital  plate  of  the  superior  maxillary  bone. 


ANATOMY    IN    A    NUTSHELL.  ")o'.l 

Insertion. — Into  the  sclerotic  coat  below  the  insertion  of  the  External 

rectus. 

Action. — It  turns  the  eye-ball  on  its  antero-posterior  axis  outward  and 
upward. 

Nerve  Supply. — Third  cranial. 

Blood  Supply. — Muscular  branches  of  the  ophthalmic  artery. 

(3)  Levator  labii  snperioris  ala^que   nasi.— 

Origin. — From  the  nasal  process  of  the  superior  maxillary  hone. 

Insertion. — Into  the  cartilage  of  the  ala  of  the  nose  and  into  the  facial 
part  of  the  Orbicularis  oris. 

Action. — Elevates  the  upper  lip  and  dilates  the  nostrils. 

Nerve   Supply. — Facial. 

Blood  Supply. — Angular  artery  from  the  facial. 

PLATE  CCLXXVII. 

TUNICA  ALBUGINEA  RECEIVING     ATTACHMENT  OF  TRABECULAE 

CONI    VASCULOSI  &m$l& COLLECTING  TUBE 


rvv^-t 


jsgp VAS     DEFERENS 


VAS  ABERRANS 


'MINOR' 
RETE  TESTIS  IN     MEDIASTINUM     TESTIS 

The  Testicle. 

(4)  Levator  anguli  oris. — 

Origin. — From  the  canine  fossa  of  the  superior  maxillary  bone. 
Insertion. — Into  the  facial  part  of  the  Orbicularis  oris. 
Action. — To  lift  the  angle  of  the  mouth. 
Nerve  Supply. — Facial. 
Blood  Supply. — Facial  artery. 

(5)  Compressor  nasi. — 

Origin. — From  the  superior  maxillary  bone  above  the  incisive  fossa. 
Insertion. — Into  the  fibro-cartilage  of  the  nose,  joining  here  its  fellow 
of  the  opposite  side  and  the  Pyramidalis  nasi. 
Action. — It  dilates  the  nostril. 
Nerve  Supply. — Facial. 
Blood  Supply. — Lateralis  nasi  of  the  facial  artery. 

(6)  Depressor  alse  nasi. — 

Origin. — From  the  incisive  fossa  of  the  superior  maxillary  bone. 
Insertion. — Into  the  septum  and  alar  cartilage  of  the  nose. 


540  ANATOMY  IN  A  NUTSHELL. 

Action.     To  contract  the  nostrils. 

Nerve  Supply. — Facial. 

Blood  Supply.—  Branches  of  the  facial. 

7     Dilator  nares  posterior. — 

Origin.— It  arises  from  the  margin  of  the  nasal  notch  and  sesamoid  car- 
tilages. 

Insertion.  —  Into  the  skin  at  the  margin  of  the  nostril. 

Action. — To   dilate  the  nostril. 

\ki;\  e  Supply. — Facial. 

Blood  Supply.  —  Branches  from  the  facial  artery. 

(8)  Massetef  muscle  which  has  been  described  on  page  520. 

(0)  Buccinator. — Description.  The  upper  and  lower  fibers  of  the  Bucci- 
nator muscle  meet  at  the  angle  of  the  month  where  they  decussate  to  he  con- 
tinuous with  the  fibers  of  the  Orbicularis  oris,  however,  the  highest  and  the 
lowest  of  these  fibers  do  not  decussate.  This  muscle,  which  is  united  with  the 
Superior  constrictor  of  the  pharynx  by  the  pterygo-maxillary  ligament,  forma 
a  muscular  wall  for  the  mouth,  while  the  Superior  constrictor  forms  a  mus- 
cular wall  for  the  pharynx. 

Origin. — From  the  posterior  areolar  processes  of  both  the  maxillary  bonea 
and  the  pterygo-maxillary  ligament. 

Insertion.—  Into  the  Orbicularis  oris  in  a  manner  which  has  been  del 
scribed  in  the  description  of  the  muscle. 

Action.-  To  compress  the  cheeks. 

Xia;\  e  Supply. — Facial,  and  buccal  branch  of  the  inferior  maxillary 
division  of  the  fifth  nerve. 

Blood  Supply. — Facial  artery. 

(10)  Internal  pterygoid  which  has  been  described  on  page  529. 

(11)  Orbicularis  oris. — Description. — The  fibers  of  this  muscle  are  de- 
rived from  the  other  facial  muscles  which  are  inserted  into  the  lips,  and  it  has 
fibers  which  belong  to  the  lip  itself.  The  fibers  which  belong  to  the  lips  pass  in 
an  oblique  direction  from  the  under  surface  of  the  skin  through  the  thickness 
of  the  lip  to  the  mucous  membrane.  Besides  these  two  sets  of  fibers  just  men- 
tioned, it  has  a  third  set  of  fibers  wheh  connect  it  with  the  superior  maxillary 
bone  :tnd    the  septum   of  the   nose. 

Origin.  By  accessory  fibers  of  nasal  septum  and  the  facial  muscles  sur- 
rounding   the    mouth. 

Insertion.  Into  the  Buccinator  and  other  muscles  surrounding  the 
mouth.      This  muscle  is  not   a  sphincter  muscle. 

ACTION.-— To   pucker  and   close1  the  mouth. 

Nerve  Supply.— Buccal  and  supramaxillary  divisions  of  the  cervico- 
facial division  of  the  seventh  nerve. 

Blood  Supply.  —  Superior  and  inferior  coronary,  and  inferior  labial. 

(12)  Levator  labil  superioris  proprius. —  DESCRIPTION. — This  muscle  covers 
the  origin  of  the  Compressor  nasi  and  Levator  anguli  oris  muscles,  and  the  in- 
fraorbital vessels  and  nerve  as  they  pass  from  the  infraorbital  foramen. 

(  )i;i<;i\.      from  the  superior  maxillary  bone  above  the  infraorbital  foramen. 


ANATOMY  IN  A    NUTSHELL.  541 

Insertion. — Into  the  upper  lip  blending  with  the  Orbicularis  oris. 

Action. — To  elevate  the  lip. 

Nerve  Supply. — Infraorbital  branch  of  the  facial. 

Blood   Supply. — Facial. 


LESSON  CLXXXIII. 

Inferior   Maxillary   Honk.     (Plates   CCLVI-CCLVII). 

The  inferior  maxillary  bone  consists  of  a  body  shaped  something  like  a 
hi nvs  shoe  with  the  ends  spread,  and  two  vertical  rami  which  meet  the  body  at 
nearly  a  right  angle.     The  body  has  the  following  points  for  consideration: 

The  external  surface  of  the  body  is  convex  from  side  to  side.  bu1  concave 
from  above  downward.  The  symphysis  is  a  vertical  ridge  in  the  middle  line 
marking  the  junction  of  the  two  lateral  portions  of  the  bone.  The  mental  pro- 
cess is  a  prominent  triangular  eminence  which  forms  the  chin.  The  incisive 
fossa  is  situated  on  each  side  of  the  symphysis  just  below  the  incisor  teeth,  ami 
jives  origin  to  the  Levator  menti  muscle.  The  Orbicularis  oris  has  an  origin 
just  externally  from  this  fossa.  The  mental  foramen  is  jusl  below  the  interval 
between  the  bicuspid  teeth  and  is  for  the  passage  of  the  mental  vessels  and 
nerve.  The  external  oblique  line  passes  outward  from  the  base  of  the  mental 
process  for  a  short  distance,  then  passes  upward  and  finally  become-  continu- 
ous with  the  anterior  border  of  the  ramus.  This  line  gives  origin  to  the  De- 
pressor labii  inferioris  and  the  Depressor  anguli  oris  muscles,  while  just  below 
it  is  attached  the  Platysma  myoides.  There  is  a  groove  near  the  anterior 
inferior  border  of  the  Masseter  muscle  for  the  facial  artery. 

The  internal  surface  of  the  body  is  concave  from  side  to  side  and  convex 
from  above  downward,  just  the  reverse  of  the  external  surface.  It  has  the 
following   points  for  consideration: 

A  depression  in  the  mid-line  corresponding  to  the  symphysis.  The  genial 
tubercles  or  mental  spin-'-  are  in  two  pairs  and  are  situated  just  below  the  center 
of  this  depression  on  either  side.  The  upper  pair  give  attachment  to  the 
Eenio-hyo-glossi,  and  the  lower  pair  give  attachment  to  the  Genio-hyoidei. 
The  sublingual  fossa,  which  is  for  the  sublingual  gland,  is  external  to  these 
tubercles  on  either  side.  Beneath  this  sublingual  fossa  at  the  lower  margin  of 
the  bone  is  the  digastric  fossa,  which  gives  attachment  to  the  Digastric  muscle. 
The  mylo-hyoid  ridge  passes  obliquely  upward  and  outward  and  gives  attach- 
ment to  the  Mylo-hyoid  muscle.  The  posterior  extremity  of  this  ridge  gives 
attachment  to  the  Superior  constrictor  muscle  and  the  pterygo-maxillary  liga- 
ment. The  submaxillary  fossa,  which  b  for  the  submaxillary  gland,  is  below 
the  mylo-hyoid  ridge.  These  oblique  line-  mi  the  external  surface  and  the  in- 
ternal surface  divide  the  body  into  an  upper  and  a  lower  portion. 

The  superior  border  of  the  body,  or  aveolar  border.  i>  thick  behind  and  has 
on  each  side  eighl  cavities  for  the  teeth,  h  gives  attachment  to  the  Buccinator 
muscle  on  its  external  surface  behind  the  first  molar  tooth. 

The  inferior  border  is  longer  than  the  superior  border  and  is  thicker  an- 
teriorly which  is  just   the  reverse  of  the  superior  border.     A  groove  for  the 


542 


ANATOMY  IN  A  NUTSHELL. 


facial  artery  is  od  this  border  at  the  function  of  the  body  with  the  ramus.     This 
groove  i-  also  partly  od  the  external  surface. 

The  rami  of  the  inferior  maxillary  bone  are  the  perpendicular  portions. 
They  arc  quadrilateral  in  shape  and  each  one  has  two  surfaces,  four  borders! 

PLATE  CCLXXVIII. 


GREAT     OMENTUM 


LEFT  COMMON  ILIAC  VEIN 


A  Sagittal  Section  of  the  Male  Organs  op  Generation. 

and  two  processes.  The  external  surface  of  the  ramus  gives  attachment  to  the 
Masseter  muscle.  The  internal  surface  of  the  ramus  lias  near  its  center  the 
inferior  dental  foramen,  which  open-  behind  the  spine.  The  mylo-hyoid 
groove  runs  obliquely  downward  from  the  dental  foramen  and  Indues  the  mylo- 


ANATOMY  IN  A  NUTSHELL.  5  !•'• 

hyoid  vessels  and  nerve.  The  Internal  pterygoid  muscle  is  attached  to  a  rough 
surface  behind  this  groove.  The  lingula  is  a  sharp  spine  at  the  anterior  margin 
of  the  mental  foramen  and  gives  attachment  to  the  internal  lateral  ligamenl  of 
the  jaw. 

The  anterior  border  of  the  ramus  is  a  continuation  of  the  external 
oblique   line. 

The  superior  border  of  the  ramus  has  the  coronoid  process  anteriorly, 
the  deep  sigmoid  notch  in  the  center,  and  the  condyle  of  the  lower  jaw  pos- 
teriorly. The  deep  sigmoid  notch  is  crossed  by  the  masseteric  vessels  and 
nerve. 

The  posterior  border,  which  is  thick  and  rounded,  is  saddled  by  the 
parotid  gland. 

The  inferior  border  is  continuous  with  the  body. 

The  angle  of  the  jaw  is  the  junction  of  the  posterior  border  and  the  in- 
ferior border.  On  the  lower  part  of  the  posterior  border  between  the  Masseter 
muscle  externally  and  the  Internal  pterygoid  muscle  internally  is  the  attach- 
ment of  the  stylo-maxillary  ligament. 

The  inferior  dental  canal,  which  is  for  the  inferior  dental  vessels  and  nerve, 
passesfrom  thedental  foramen  in  the  ramusof  the  bone  downward  and  forward. 
It  now  turns  forward  to  pas-  underthe  alveoli  in  the  body  of  thebone  as  far  as 
the  incisor  teeth.  It  gives  off  a  branch  to  the  mental  foramen.  This  canal 
lies  near  the  internal  surface  of  the  bone  for  its  first  two-thirds,  and  near  the 
external  surface 'for  its  anterior  one-third. 

The  coronoid  process,  which  is  at  the  anterior  margin  of  the  upper  border 
of  the  ramus,  is  thin.  flat,  and  triangular.  It  gives  attachment  to  the  Tem- 
poral muscle  on  both  its  external  and  interna]  surface-. 

The  condyloid  process  is  situated  at  the  posterior  margin  of  the  superior 
border  of  the  ramus.  Its  condyle,  winch  has  its  long  axis  transversely  and 
its  outer  end  higher  and  more  anterior  than  the  inner,  articulates  with  the 
glenoid  fossa  of  the  temporal  bone.  The  neck  of  the  condyloid  process  receives 
the  insertion  of  the  External  pterygoid  muscle  internally.  There  is  a  tubercle 
on  its  external  margin  for  the  capsular  and  external  lateral  ligamenl  of  the 
lower  jaw. 

Ossification. — This  bone  ossifies  from  twelve  centers;  six  for  each  lateral 
half. 

Articulation. — It  articulates  with  the  glenoid  fossa'  of  the  two  temporal 

bone-. 

Attachment  of  Muscles.  Thee  are  fifteen  pairs  of  muscles  attached  to 
this  hone.  To  the  kames.  the  Masseter  of  the  teniporo-niaxillarv  region,  the 
Internal  pterygoid  and  External  pterygoid  of  the  pterygo-maxillary  region, 
and  Temporal  of  the  temporo-maxillary  region;  to  internal  surfaci 
ok  'nil-:  body,  the  Genio-hyo-glossus  and  Genio-hyoideus  of  the  lingual  region, 
Mylo-hyoid  of  the  supra-hyoid  region,  Digastric  of  the  supra-hyoid  region,  and 
Superior  constrictor  of  the  pharynx  :  ro  the  extern  ^l  surfaci  of  the  body, 
Depressor  lahii  Lnferioris  and  Depressor  anguli  oris  of  the  inferior  maxillary 
region,  Levator  menti  of  the  inferior  maxillarv  region.     Orbicularis  oris  of  the 


.",44  ANATOMY  IX  A  XUTSHELL. 

intermaxillary  region,  Platysma  myoides  of  the  superficial  cervical  region,  and 
Buccinator  of   the   intermaxillary   region. 

Blood  Supply. — Branches  from  the  internal  maxillary. 

LESSON   CLXXXIV. 

1.  Masseter  muscle  which  has  been  described  on  page  o'20. 

2.  Internal  pterygoid  which  has  been  described  on  page  529. 
.!.  External  pterygoid  which  has  been  described  on  pane  529. 
4.  Temporal  muscle  which  has  been  described  on  page  508. 

.").  Genio-hyo-glossus. — Description. — This  muscle  is  fan-shaped  and 
placed  vertically  on  either  side  of  the  middle  line  of  the  jaw.  The  apex  of  this 
muscle  is  at  its  point  of  attachment  to  the  lower  jaw  and  its  base  is  its  insertion 
into  the  tongue  and  the  hyoid  hone.  This  muscle  is  more  or  less  blended  with 
its  fellow  in  front  but  separated  from  it  behind. 

Origin. — From  the  superior  genial  tubercle  on  the  inner  side  of  the  sym- 
physis of  the  jaw. 

1  NSERTK  in.  Into  the  upper  part  of  the  body  of  the  hyoid  bone  and  median 
line  of  the  tongue,  the  side  of  the  pharynx,  and  the  entire  length  of  the  under 
surface  of  the  tongue. 

Action.— To  retract    and   protrude  the  tongue. 

Xki;\  e  Supply. — Hypoglossal. 

Blood  Si  pply. — Lingual. 

(>.  Genio-hyoideus. — Description. — This  muscle  increases  in  breadth  as 
it  pa>ses  towards  its  insertion  and  lies  close  to  its  fellow.  It  is  situated  be- 
neath the  inner  border  of  the  Mylo-hyoid. 

Origin.—  From  the  inferior  genial  tubercle  of  the  lower  jaw. 

Insertion. — Into  the  anterior  surface  of  the  body  of  the  hyoid  bone. 

A'  tion.     To  lift  and  draw  forward  the  hyoid  bone. 

Nerve  Supply. — Hypoglossal. 

Blood  Supply. — Lingual. 

7.  Mylo-hyoid. — 

Origin. — From  the  mylo-hyoid  ridge  of  the  lower  jaw. 
Insertion.      Into  the  body  of  the  hyoid  bone  and  a  median  fibrous  raphe 
running  in  mid-line  of  the  hyoid  bone  to  the  chin. 

V  ii"\.      Lift-   the  hyoid  and  draws  it   forward. 

N  i  i:\  i.  Si  pply.-  -Mylo-hyoid  branch  of  the  inferior  dental  of  the  fifth. 

Blood  Supply.     Submental  and  mylo-hyoid  arteries. 

8.  Digastric  muscle  which  has  been  described  on  page  521. 

9.  Superior  constrictor  which  has  been  described  on  page  515. 
in.   Depressor  labii  int'erioris,  also  called  Quadratus  menti. 

Origin.  From  the  external  oblique  line  of  the  inferior  maxillary  bone 
below  and  internal  to  the  mental  foramen. 

Insertion.  —  Into  the  lower  lip  (facial  pari  of  the  Orbicularis  oris). 

Action.     To  draw  the  lower  lip  down. 

Nerve  Si  pply.     Supramaxillary  branch  of  facial  nerve. 


ANATOMY  IX  A  NUTSHELL. 


545 


Blood  Supply. — Branches  from  the  facial  artery. 
11.  Depressor  anguli  oris  (also  called  Triangularis  nienti). 
Origin. — From  the  external  oblique  line  of  the  inferior  maxillary  bone 
between  the  attachments  of  the  Depressor  iabii  inferioris  and  Platysma  myoides. 
Insertion. — Into  the  angle  of  the  mouth. 
Action. — To  draw  down  the  angle  of  the  mouth. 
Xerve  Supply. — Supramaxillarv  division  of  the  facial. 
Blood  Supply. — Branches  of  the  facial  artery. 

PLATE  CCLXXIX. 


AMPULLA  OF  DUCT 


ACINI  OF  (HAND 


ADIPOSE  LOCULUS 


MAMMILLA 


AREOLA 


GLAND  LOCULUS 

The  Mammary  ( }land. 

12.  Levator  labii  inferioris,  also  called  Levator  menti. 

Origin. — From  the  incisive  fossa  of  the  inferior  maxillary  bone. 
Insertion.  —  Into  the  facial  pari  of  the  Orbicularis  oris  and  internment 
of  chin. 

Action.-    To  raise  the  lower  lip. 

Nerve  Supply. — Supramaxillarv  branch  of  the  seventh. 

Blood  Supply.     Branches  of  the  facial   artery. 

13.  Orbicularis  oris  which  has  been  described  on  page   540. 

14.  Platysma  inyoides.     Description.     The   Platysma   myoides,  which  i^ 
a  broad  thin  layer  of  muscle,  lies  in  the  superficial  fascia. 

Ork;ix. — From  the  dee])  fascia  which  covers  the  Deltoid  and  Pectoralis 


546  ANATOMY  IN  A  NUTSHELL. 

major  muscles,  as  it  passes  over  the  clavicle  a  few  fibers  may  be  attached  to  it. 
Insertion. — Into  the  fascia  extending  from  the  angle  of  the  mouth  to 
the  angle  of  the  jaw,  also  into  the  inferior  maxillary  bone  below  the  mental 
foramen. 

A.CTION.       Helps   to   depress  the  lower  jaw. 

Nerve  Supply. — The  inframaxillary  division  of  the  seventh. 
Blood  Supply. — Branches  of  the  external  carotid  artery. 
15.  Buccinator  which  has  been  described  on  page  540. 


LESSON  CLXXXV. 
[nferioe  Turbinated  Bone.     (Plates  CCLX-CCLXIV.) 

The  inferior  turbinated  bone,  which  is  situated  in  the  nasal  fossa  along  its 
outer  wall,  is  curved  upon  itself.  It  has  two  surfaces,  two  borders,  two  ex- 
tremities,  and    three   processes. 

The  external  surface  of  the  inferior  turbinated  bone  is  concave,  ami  helps 
to   form    the   inferior   meatus. 

The  internal  surface  of  the  inferior  turbinated  bone  is  convex. 

The  extremities  of  this  bone  are  narrow  and  pointed. 

The  inferior  border  (free  border)  passes  to  within  half  an  inch  of  the  floor 
of    the   nose. 

The  superior  border  articulates  with  the  inferior  turbinated  crest  of  the 
superior  maxillary  bone  anteriorly,  and  with  the  inferior  turbinated  crest  of 
the  palate  bone  posteriorly. 

The  lachrymal  process  is  on  the  superior  border  at  the  junction  of  the 
anterior  one-fourth  with  the  posterior  three-fourths.     It  articulates  with  the 
inferior  angle  of  the  lachrymal  bone  and  also  with  the  nasal  process  of  the 
superior  maxillary  bone,  thus  helping  to  form  the  nasal  duct. 

The  ethmoidal  process  is  on  the  superior  border  about  half  way  between 
the  lachrymal  process  and  the  posterior  extremity  of  the  bone.  It  articulates 
with  the  unciform  process  of  the  ethmoid. 

The  maxillary  process,  which  is  immediately  below  the  ethmoidal  process 
but  on  the  external  surface  of  the  bone,  articulates  with  the  lower  edge  of  the 
aperature  of  the  antrum  of  Eighmore,  and  also  helps  to  close  this  opening. 

Ossification.-   It  ossifies  from  one  center. 

Articulation. — It  articulates  with  four  bones.  The  ethmoid  of  the 
cranium,  superior  maxillary,  lachrymal,  and  palate  of  the  face. 

Attachment  of  Muscles. — It  has  no  muscles  attached  to  it. 

Bl< m >i>  Si  pply. — 

Vomer    Bone.     (Plate  CCLXI). 

The  vomer  (ploughshare)  forms  the  postero-inferior  part  of  the  nasal 
septum  and  is  a  single  bone.     It  has  the  following  points  for  consideration: 

The  oaso-palatine  grooves  or  canals  are  situated  on  each  side  of  this  hone 
running  downward  and  forward  to  the  intermaxillary  suture.  They  are  for 
the  naso-palatine  nerves. 

The  posterior  border  of  the  vomer  is  concave  and  free.  Its  lower  portion 
is  thin,  while  its  upper  portion  is  divided. 


ANATOMY    IX    A    NUTSHELL.  547 

The  inferior  border,  which  is  the  longest,  articulates  with  the  nasal  cresl 
of  the  superior  maxillary  and  palate  bone. 

The  anterior  border  is  short  and  articulates  with  the  incisor  crests  of  the 
superior  maxillary  bone. 

The  antero-superior  border  receives  the  Lower  margin  of  the  triangular 
cartilage  below  and  the  vertical  plate  of  the  ethmoid  above. 

The  postero-superior  border  is  the  thickest  and  has  a  median  groove  which 
receives  the  rostrum  of  the  sphenoid  bone.  This  border  is  bounded  on  either 
side  by  the  ala,  which  fits  in  the  vaginal  process  of  the  sphenoid.  This  joint 
is  a  schindylesis. 

OSSIFICATION. — This  bone  ossifies  from  one  center. 

Articulation. — It  articulates  with  six  bones.  The  sphenoid  and  ethmoid 
of  the  cranium,  the  two  superior  maxillary,  the  two  palate  of  the  face.  It  also 
articulates  with  the  cartilage  of  the  septum. 

Attachment  of  Muscles. — It  has  no  muscles  attached  to  it. 

Blood  Supply. — Anterior  and  posterior  ethmoidal,  and  nasopalatine 
through  Stenson's  canal. 


LESSON  CLXXXVI. 

Palate  Bone.     (Plates  CCLXII-CCLXIII-CCXXVIII-CCXXIX). 

The  palate  bones  are  two  in  number  and  situated  between  the  superior 
maxillary  bones  and  the  pterygoid  processes  of  the  sphenoid  bone  at  the  back 
of  the  nasal  fossae.  Each  bone  helps  to  form  the  roof,  floor,  and  outer  wall  of 
the  nose,  and  the  floor  of  the  orbit.  They  also  help  to  form  the  spheno-max- 
illary  fissure,  spheno-maxillary  fossa,  and  the  pterygoid  fossa,  and  the  zygo- 
matic fossae.     Each  one  has  the  following  points  for  consideration: 

The  horizontal  plate,  which  is  thick,  has  two  surfaces  and  four  borders. 

The  superior  surface  is  concave  transversely  and  forms  the  back  part  of 
the  floor  of  the  nose. 

The  inferior  surface  is  also  concave  and  forms  the  back  pail  of  the  hard 
palate,  and  has  upon  it  a  transverse  ridge  for  the  attachment  of  the  Tensor 
tympani  aponeurosis.  A  groove  is  situated  at  the  outer  end  of  this  transverse 
ridge  which  with  the  tuberosity  of  the  superior  maxillary  bone  forms  the  pos 
terior  palatine  canal.  Posterior  to  this  groove  are  foramina  of  the  accessory 
posterior  palatine  canals. 

The  anterior  border  is  serrated  ami  articulates  with  the  palate  process  of 
the  superior  maxillary  bone. 

The  internal  border  is  thick  and  articulate-  with  the  internal  border  of  it- 
fellow,  thus  forming  a  groove  on  the  upper  surface  for  the  reception  of  the 
vomer.  On  the  posterior  extremity  of  this  border  is  a  posterior  nasal  -pine 
which  is  for  the  origin  of  the  Azygos  uvula-  muscle. 

The  external  border  joins  the  verl  Leal  plate  of  the  palate  bone  at  righl  angle. 

The  posterior  border  is  free  and  concave,  and  gives  attachment  to  the  soft 
palate. 


548  ANATOMY    IN    A    NUTSHELL. 

The  vertical  plate  is  broad  and  thick  and  is  directed  upward  and  slightly 
inward.     This  plate  has  two  surfaces  and  four  borders. 

The  external  surface  articulates  with  the  superior  maxillary  bone  for  most 
of  its  extent.  This  pari  of  the  hone  is  rough.  The  front  part  of  this  surface 
is  smooth  and  covers  the  orifice  of  the  antrum  of  Highmore.  The  upper  and 
back  part  of  this  surface  helps  to  form  the  spheno-maxillary  fossa  and  is  also 
smooth.  On  the  posterior  part  of  this  surface  is  a  deep  groove  which  with  the 
superior  maxillary  hone  forms  the  posterior  palatine  canal  for  the  descending 
palatine  vessels  and  the  descending  palatine  nerve. 

The  internal  surface  forms  part  of  the  inferior  meatus  which  is  below  the 
inferior  turbinated  crest.*  The  superior  turbinated  crest  articulates  with  the 
middle  turbinated  hone,  and  above  this  crest  is  the  superior  meatus,  while 
between  this  crest  and  the  inferior  turbinated  crest  is  the  middle  meatus. 

The  inferior  border  joins  the  horizontal  plate  at  right  angles. 

PLATE  CCLXXX. 


The  Outee  Surface  of  the  Pinna. 

The  superior  border  has  a  notch  separating  the  sphenoidal  process  from 
i  he  orbital  process,  and  this  notch  is  converted  into  the  spheno-palatine  foramen 
by  the  sphenoidal  turbinated  bone.  The  spheno-palatine  vessels  and  the 
superior  nasal  and  naso-palatine  oerves  pass  through  this  foramen.  It  was 
stated  above  that  this  notch  was  converted  into  a  foramen  by  the  sphenoidal 
turbinated  bone,  but  it  may  be  convened  into  a  foramen  by  the  two  processes 
meet  ing. 

The  anterior  border  has  the  maxillary  process  at  the  anterior  extremity 
of  tlw  inferior  turbinated  crest.  This  process  closes  the  antrum  of  Highmore 
posteriorly  and  inferiorly.     This  border  articulates  with  the  superior  maxillary 

I  MlllC. 

The  posterior  border  has  a  deep  groove  and  articulates  with  the  pterygoid 
process  of  the  sphenoid  bone.  The  Internal  pterygoid  muscle  has  part  of  its 
origin  from  a  median  groove  on  the  lower  pari  of  this  border  which  forms  part 
of   the   pterygoid    process. 

The  orbital  process  is  triangular  in  shape  and  is  directed  upward  and  out- 


ANATOMY     IX    A     NUTSHELL.  549 

ward.  It  has  three  articular  surfaces  and  two  free  surfaces.  The  articular 
surface-  are  the  anteriob  or  maxillary,  which  articulates  with  the  superior 
maxillary  bone. — internal  or  ethmoidal  surface,  which  articulates  with  the 
ethmoid  hone. — and  posterior  or  sphenoidal  surface,  winch  articulate.-  with 
the  sphenoidal  turbinated  bone.  The  free  surfaces  are  the  orbital,  which 
forms  part  of  the  Moor  of  the  orbit. — ami  Tin:  external  or  zygomatic  surface, 
which  forms  part  of  the  zygomatic  fossa.  This  process  has  a  rounded  border 
which  forms  part  of  the  spheno-maxillary  fissure. 

The  sphenoidal  process  is  -mailer  than  the  orbital  process  and  articulates 
.superiorly  with  the  body  of  the  sphenoid,  and  externally  with  the  pterygoid 
process  of  the  sphenoid.  It  has  three  surfaces  and  two  borders.  Tin:  internal 
surface,  which  is  concave,  forms  part  of  the  outer  wall  of  the  nasal 
fossa— the  superior  surface,  which  articulates  with  sphenoidal  turbi- 
nated bone,  is  converted  into  the  pterygo-palatine  canal, — Tin:  external 
surface  articulates  with  the  inner  surface  of  the  pterygoid  process  of  the 
sphenoid  bone,  and  also  help.-  to  form  the  spheno-maxillary  fossa.  Its  ANTER- 
IOR border  forms  the  back  part  of  the  spheno-palatine  foramen.  Its  pos- 
terior border  articulates  with  the  inner  surface  of  the  pterygoid  process. 

Ossification. — This  bone  ossifies  from  one  center. 

Articulation. — It  articulates  with  six  bones.  The  sphenoid,  ethmoid, 
superior  maxillary,  inferior  turbinated,  vomer,  and  its  fellow. 

Attachment  of  Muscles. — This  bone  has  four  muscles  attached  to  it. 
The  Tensor  palati  of  the  soft  palate.  Azygos  uvulae  of  the  soft  palate.  Internal 
pterygoid  of  the  pterygo-maxillary  region,  and  Superior  constrictor  of  the 
pharynx. 

Blood  Supply. — Descending  palatine,  spheno-palatine,  and  pterygo- 
palatine. 

1.  Tensor  palati,  which  has  been  described  on  page  522. 

2.  Internal  pterygoid  muscle,  which  has  been  described  on  page 529. 

3.  Azygos  uvulae. — Description. — There  is  a  pair  of  these  muscles  although 
from  the  name  we  might  think  there  is  but  one.  There  is  one  on  each  side 
of  the  median  line  of  the  soft  palate. 

Origin. — From  the  nasal  spine  of  the  palate  bone  and  the  adjacent  apo- 
eurosis  of  the  soft    palate. 

I  nsertk  i\.      Into  the  uvula. 

Action. — To  shorten  the  uvula. 

Nerve  Supply.—  Internal  branch  of  spinal  accessory,  through  the  pharyn- 
geal plexus. 

Bloob  Supply. — Palatine  arteries  from  internal  maxillary. 

4.  Superior  constrictor,  which  has  been  described  on  page  515 


LESSON  CLXXXVII. 
Hyoid  Bone.     (Plate  XIX). 
The  hyoid  bone,  which  is  situated  a1  the  base  of  the  tongue  consists 
body,  two  greater  cornua,  two  lesser  cornua,  making  it  horse-shoe  in  shape. 

It  is  called  the  lingual  bone.     The  anterior  surface  of  tin-  body  is  convex  and 


550  .  AX  ATOMY    IX    A    XUTSHELL. 

has  a  ventral  ridge  in  its  center.  There  is  a  small  tubercle  on  the  upper  end  of 
this  ridge.  This  surface  has  attached  to  it  the  following  muscles:  Genio- 
hyoid. Genio-hyo-glossus,  Hyo-glossus,  Mylo-hyoid,  Stylo-hyoid,  the  aponeu- 
rosis of  the  Digastric  muscle. 

The  posterior  surface  of  the  hotly  is  concave. 

The  lateral  surfaces  articulate  with  the  greater  cornua. 

The  superior  surface  gives  attachment  to  the  Genio-hyo-glossus,  and 
( Jhondro-glossus. 

The  inferior  border  gives  attachment  to  the  Sterno-hyoid,  Omo-hyoid,  and 
Thyro-hyoid  muscles.     All  muscles  attached  to  this  hone  are  in  pairs. 

The  greater  cornu  projects  backward  and  outward  from  the  lateral  sur- 
face of  the  body.  The  thyro-hyoid  ligament  is  attached  to  the  end  of  the 
greater  cornu.  The  Hyo-glossus  muscle  is  attached  to  its  outer  surface, the 
Middle  consl  rictor  to  its  upper  border,  and  the  Thyro-hyoid  to  its  lower  border. 

The  lesser  cornu  is  situated  at  the  angle  where  the  greater  cornu  joins  the 
hotly.  The  stylo-hyoid  ligament  is  attached  to  its  apex.  This  articulation 
may  he  ankylosed  hut  is  generally  free. 

Ossification. — From  five  centers. 

Articulation. — It   articulates  with  no  bone. 

A  it  \i  hment  of  Muscles. — This  bone  has  twelve  pairs  of  muscles  attached 
to  it,  as  well  as  the  thyro-hyoid  membrane  and  the  stylo-hyoid,  thyro-hyoid, 
and    hyo-epiglottic   ligaments. 

Blood  Supply. — Superior  thyroid  and  lingual  of  the  external  carotid 
artery. 

1.  Sterno-hyoid  muscle,  which  has  been  described  on  page  40. 

2.  Thyro-hyoid. — 

Origix. — From  the  oblique  line  on  the  thyroid  cartilage. 

Insertion.-    Into  the  body  and  the  greater  cornu  of  the  hyoid  bone. 

Action. — To  depress  the  larynx  and  the  hyoid  hone. 

Nerve  Supply. — Hypoglossal  nerve. 

Blood  Supply. — Superior  thyroid  artery. 

'■'•.  Omo-hyoid  muscle,  which  has  been  described  on  page  59. 

4.  Digastric  muscle,  which  has  been  described  on  page  521. 

5.  Stylo-hyoid,  which  has  been  described  522. 

6.  Mylo-hyoid,  which  has  been  described  on  page  544. 

7.  Genio-hyoid,  which  has  been  described  on  page  544. 

8.  Genio-hyo-glossus,  which  has  been  described  on  page  544. 

o.  Chondro-glossus.-  Description.— This  muscle  is  sometimes  described 
as  pari   of  the  Hyo-glossus. 

Origin.     From  the  body  and  lesser  cornu  of  the  hyoid  bone. 

Insertion.  Ento  the  intrinsic  muscles  of  the  tongue  between  the  Hyo- 
glossus  ami  the  Genio-hyo-glossus. 

Action.     To  draw  down  tin-  side  of  the  tongue. 

\i.i;\  e  Supplj  .-  -Hypoglossal. 

I'.i.t  k  >n  Si  ppl"5  .     Lingua]  artery. 

Hi.  Byo-glossus. 


ANATOMY    IN"    A    NUTSHELL. 


551 


Origin. — From  the  whole  length  of  the  greater  cornu  and  from  the  body 
of  the  hyoid  bone. 

[nsertion. — Into  the  side  of  the  tongue. 

Action. — To  draw  down  the  side  of  the  tongue. 

Nerve  Supply. — Hypoglossal. 

Blood  Supply. — Lingual  artery. 

]  1 .  Middle  constrictor. — 

Origin. — From  the  greater  cornu  of  the  hyoid  Ik  die  and  the  stylo-hyoid 
ligament. 

Insertion. — Into  the  middle  line  of  the  pharynx  by  the  fibrous  raphe. 

Action. — To  constrict  the  pharynx  antero-posteriorly. 

Nerve  Supply. — Pharyngeal  plexus. 

PLATE  CCLXXXI. 


DUCTUS  ENDOLYMPHATIC!.)";      TYMPANIC  CAVITY 


SACCULE 


EUSTACHIAN  TUBE'!  1/1  4 
MEMRRANA  TYMPANI 
EXT   AUDITORY  MEATUS 


Diagrammatic  View  of  the  Organs  of  Eearing. 
(Modified  prom  Cunningham.) 

Blood  Supply. — Same  as  the  blood  supply  to  the  pharynx,  which  is  given 
on  page  315. 

^'2.  Inferior  Ungualis, — This  muscle  runs  along  the  under  edge  of  the 
tongue  in  its  whole  length,  h  makes  the  dorsum  convex  and  shortens  the 
tongue. 


LESSON   CLXXXVIII. 
There  auk  three  Pairs  of  Meati  ses  i\  the  Nose.     (Plate  CCLXIV). 

The  superior  meatus,  which  is  the  smallest  of  the  three,  is  situated  be- 


552  ANATOMY    IN    A    NUTSHELL. 

tweeD  the  superior  turbinated  bone  and  middle  turbinated  bone  at  the  upper 
and  back  pari  of  tin-  nasal  fossa.  This  meatus  occupies  the  posterior  one-third 
of  the  outer  wall  of  the  nasal  fossa.  The  spheno-palatine  foramen  opens  into 
it  at  the  back  part  of  its  miter  wall,  while  the  posterior  ethmoidal  cells  open  into 
it  at  the  anterior  part  of  the  outer  wall.  The  spheno-ethmoidal  recess  is  be- 
hind the  superior  turbinated  bone  at  the  superior  and  posterior  part  of  the 
nasal  fossa  and  opens  into  the  sphenoidal  sinus. 

The  middle  meatus  occupies  the  posterior  two-thirds  of  the  outer  wall  of 
the  nasal  fossa  and  is  situated  between  the  middle  turbinated  bone  and  the 
inferior  turbinated  bone.  This  meatus  communicates  anteriorly  with  the 
anterior  ethmoidal  cells  by  means  of  the  infundibulum  and  through  these  cells 
with  the  frontal  sinus.  The  opening  of  the  antrum  of  Highmore  is  near  the 
center  of  this  meatus. 

The  inferior  meatus,  which  is  the  largest  of  the  meatuses,  is  situated  be- 
tween the  inferior  turbinated  bone  and  the  floor  of  the  nasal  fossa.  It  will 
be  noticed  that  the  superior  meatus  occupied  the  posterior  one-third  of  the 
outer  wall  and  the  midlle  meatus  occupied  the  posterior  two-thirds  of  the 
outer  wall,  while  the  inferior  meatus  occupiesthe  entire  length  of  the  outerwall 
of  the  nasal  fossa.  The  canal  for  the  nasal  duct  opens  at  the  anterior  extremity 
of  this  meatus. 

The  nasal  fossae  extend  from  the  base  of  the  cranium  to  the  roof  of  the 
mouth,  and  are  situated  on  each  side  of  the  middle  line  of  the  face.  They  are 
two  large  cavities  which  are  separated  from  each  other  by  a  thin  septum.  The 
anterior  nares  open  on  the  front  of  the  face  from  the  nasal  fossa'  while  the  pos- 
terior nares  open  into  the  pharynx.  The  frontal  sinus  communicates  with 
the  nasal  fossa  above,  the  sphenoidal  sinus  communicates  with  the  nasal  fossa 
posteriorly,  and  the  antrum  of  Highmore  and  the  ethmoidal  sinus  communi- 
cate with  it  externally.  The  orbit  is  joined  to  the  nasal  fossa  by  the  lachry- 
mal groove.  The  mouth  communicates  with  the  nasal  fossa  by  the  anterior 
palatine  canal.  The  cranium  communicates  with  the  nasal  fossa  by  the  ol- 
factory  foramina,  and  the  spheno-maxillary  fossa  communicates  with  the  nasal 
fossa  by  the  spheno-palatine  foramen.  Sometimes  the  nasal  fossae  communi- 
cate with  each  other  by  an  opening  in  the  septum.  There  are  fourteen  bones 
in  the  nasal  fossae.  They  include  all  the  bones  of  the  face  except  the  two  malar 
and  the  inferior  maxillary,  and  in  place  of  these  three  it  has  the  frontal,  eth- 
moid and  sphenoid  of  the  crainum.  The  ethmoid  bone  with  all  its  articu- 
lation- make  the  nasal  fossa-.  The  frontal,  ethmoid,  and  sphenoid  are  com- 
mon  to  the  nasal  fossa,  cranium  and  the  orbits. 

There  are  numerous  foramina  at  the  base  of  the  skull  extending  from  the 
foramen  csecum  to  the  foramen  magnum.  There  are  also  three  large  fossae  at 
the  base  of  the  skull,  namely,  the  anterior  fossa,  middle  fossa,  ami  the  posterior 
fossa.     (Plate  CCXXXV.) 

Till.    WTI.imu;    FOSSA    HAS  THE    FOLLOWING    FORAMINA: 

1.  Foramen  caecum  through  which  a  vein  passes  to  the  superior  longitu- 
dinal sinus,  sometimes  one  from  the  frontal  sinus.  This  is  a  single  foramen, 
while  the  others  in   this  fossa  arc  in   pair-. 


ANATOMY    IN    A    NUTSHELL.  553 

2.  The  ethmoidal  fissure  through  which  passes  the  nasal  nerve  and  the 
anterior  ethmoidal  vessels. 

3.  Olfactory  foramina  for  the  olfactory  nerves  and  nasal  branches  of  the 
ethmoidal  arteries. 

4.  Anterior  ethmoidal  foramen  for  anterior  ethmoidal  vessels  and  nasal 
nerve. 

5.  Posterior  ethmoidal  foramen  for  posterior  ethmoidal  vessels  and  a  branch 
of  the  nasal  nerve. 

6.  Optic  foramen  for  the  opticnerve  and  the  ophthalmic  artery.  Thisfor- 
amen  is  sometimes  given  as  belonging  to  the  middle  fossa  since  it  is  <>n  the 
boundary  line  between  the  anterior  and  middle  fossa.  Thus  we  can  see  that 
there  are  eleven  sets  of  foramina  in  the  anterior  fossa ;  five  pairs  and  a  single  one. 


LESSON  CLXXX1X. 
The  middle  fossa  is  on  a  lower  level  than  the  interior  fossa   wn 

HAS  THE  FOLLOWING  FORAMINA  ALL  OF  WHICH  ARE  IN  PAIRS: 

1.  Sphenoidal  fissure  (anterior  lacerated  foramen)  winch  transmits  the 
third  nerve,  the  fourth  nerve,  and  three  divisions  of  the  ophthalmic  division 
of  the  fifth  nerve,  and  the  sixth  nerve,  also  filaments  from  the  cavernous  plexus. 
ophthalmic  vein,  recurrent  branch  from  the  lachrymal  artery,  orbital  branch 
of  the  middle  meningeal  artery,  and  a  process  of  the  dura  mater. 

2.  Foramen  rotundum  through  which  passes  the  superior  maxillary  divi- 
sion of  the  fifth  nerve. 

3.  Foramen  Vesalii  which  is  for  a  small  vein. 

4.  Foramen  ovale  through  which  passes  the  inferior  maxillary  division  of 
the  fifth  nerve,  small  petrosal  nerve,  and  the  small  meningeal  artery. 

5.  Foramen  spinosum  through  which  passes  the  middle  meningeal  artery, 
meningeal  veins,  and  filaments  from  the  cavernous  plexus. 

6.  Foramen  laeerum  medium  through  which  passes    the  vidian   nerve,  a 
branch  from  the  ascending  pharyngeal  artery,  carotid  artery,  and  carotid  plexus. 

7.  Hiatus  Fallopii  through  which  passes  the  petrosal  branch  of  the  vidian 
nerve  and  the  petrosal  branch  of  the  middle  meningeal  artery. 

8.  A  small  foramen  through  which  passes  the  lesser  petrosal  nerve.  Thus 
we  see  there  are  sixteen  sets  of  foramina  in  the  middle  fossa. 

The  posterior  FOSSA   is  ox  a   deeper  level  than   either  of  the  other 

FOSSAE  AND  CONTAINS  THE  CEREBELLUM  AND  THE  MIDDLE  FOSSA  CONTAINS 
TEMPORO-SPHENOIDAL LOBES  OF  THECEREBRUM  AND  THE  INTERIOR  FOSSA  CON- 
TAINS THE  FRONTAL  LOBES  OF  THE  CEREBRUM.  THIS  FOSSA  HAS  THE  FOLLOW- 
ING foramina: 

1.  The  meatus  auditorius  interims  for  the  facial  and  auditory  nerves  and 
the    auditory    artery. 

2.  The  aqueductus  vestibuli  is  for  a  small  artery  and  vein  and  pri 
the  dura  mater. 

3.  The  jugular  foramen  (foramen  laeerum  posterius)  in  which  there  are 
three  compartments,   through   the  anterior  one  of  which   passes  the  inferior 


554  ANATOMY    IN    A    NUTSHELL. 

petrosal  sinus,  through  the  middle  one  passes  the  glosso-pharyngeal,  pneumo- 
gastric,  and  spinal  accessory  nerves,  through  the  posterior  one  the  lateral 
sinus,  and  meningeal  branches  of  the  occipital,  and  ascending  pharyngeal 
arteries. 

4.  Mastoid  foramen  (often  absent)  is  for  a  small  vein  and  sometimes  the 
mastoid  artery. 

.">.  The  anterior  condyloid  foramen  which  is  for  the  hypoglossal  nerve,  and 
meningeal  branches  of  the  ascending  pharyngeal  artery. 

(i.  The  posterior  condyloid  foramen  (often  absent)  for  posterior  condyloid 
vein. 

7.  Foramen  magnum  which  transmits  the  medulla  oblongata  and  its 
membranes,  spinal  accessory  nerves,  vertebral  arteries,  anterior  and  posterior 
spinal  arteries,  and  the  occipito-axial  ligaments.     This  foramen  is  a  single  one 

PLATE  CCLXXXII. 


HELIX 
ANTI-    HELIX 


A\  \\\   |  u 

ATTOLLENS  AURICULAI 

ma  fa 


ml  ';'//  f& 

fk  \\    |  '  /  ///'       /    ATTRAHENS    AURICULAM 


OBLIOUUS  AURICULAM 


EXTERNAL      AUDITORY      MEATUS    -  ^ARTIUGINEUS 

Posterior  View  of  the  Ear  With  Auricular  Muscles. 

and  the  others  are  in  pairs.  Thus  we  see  there  are  thirteen  foramina  in  the 
posterior  fossa.  The  eleven  in  the  anterior  fossa,  and  sixteen  in  the  middle 
fossa,  and  the  thirteen  in  the  posterior  fossa  make  the  forty  foramina  at  the 
base   of    the   -hull. 


lesson  cxc. 

The  temporal  fossa  (Plate  CCXXXIV)  is  hounded  anteriorly  by  the  ex- 
ternal angular  process  of  the  frontal  bone,  superiorly  by  the  temporal  ridges, 
posteriorly  by  the  temporal  ridges,  inferiorly  by  the  zygomatic  arch.  This 
fossa  is  separated  from  the  zygomatic  fossa  by  tin1  pterygoid  ridge  which  is 
on  the  outer  surface  of  the  greater  wing  of  the  sphenoid  hone.  The  temporal 
fossa  is  formed  by  five  hone-,  ill  pari  of  the  frontal  hone,  (2)  greater  wing  of 
the  sphenoid  hone.  (3)  pari  of  the  parietal  hone.  (4)  squamous  portion  of  the 
temporal,  (5)  malar  bone.  It  has  the  following  sutures:  (1)  a  part  of  the  trans- 
verse facial  -uture.  ("_M  spheno-malar  suture,  (3)  coronal  suture,  (4)  spheno-pari- 


ANATOMY    IN    A    NUTSHELL.  ■>•>•> 

etal  suture,  (5)  squamo-parietal   suture,  (6)  squamo-sphenoidal  suture. 

The  stephanion  is  the  point  where  the  coronal  suture  meets  the  temporal 
ridge. 

The  pterion  is  the  point  where  the  parietal,  frontal,  squamous  portion  of 
the  temporal,  and  the  greater  wing  of  the  sphenoid  meet. 

The  temporal  fossa  is  deep  and  concave  anteriorly,  but  convex  posteriorly. 
It  is  marked  by  grooves  which  lodge  branches  of  the  deep  temporal  arteries. 
The  Temporal  muscle  fills  this  fossa. 

The  zygomatic  fossa  is  bounded  anteriorlyby  the  tuberosity  of  thesuperior 
maxillary  bone,  posteriorly  by  the  eminentia  articularis  and  the  posterior  bor- 
der of  the  external  pterygoid  process,  superiorly  by  the  pterygoid  ridge  which 
is  on  the  outer  surface  of  the  greater  wing  of  the  sphenoid  hone  and  separates 
this  fossa  from  the  temporal  fossa,  interiorly  by  the  alveolar  border  of  the  super- 
ior maxillary  bone,  externally  by  the  zygomatic  arch  and  the  ramus  of  the  lower 
jaw,  internally  by  the  external  pterygoid  plate.  The  internal  maxillary  artery, 
the  inferior  maxillary  nerve  ami  its  branches,  the  External  pterygoid  muscle. 
the  Internal  pterygoid  muscle,  and  the  lower  pan  of  the  Temporal  muscle  are 
situated  in  this  fossa.  The  spheno-maxillary  fissure  ami  the  pterygo-maxillary 
fissure  are  at  the  superior  and  internal  part  of  this  fossa. 

The  spheno-maxillary  fissure,  which  opens  into  the  outer  and  back  part 
of  the  orbit,  is  horizontal  in  direction  and  is  formed  by  the  lower  border  of  the 
orbital  surface  of  the  greater  wing  of  the  sphenoid  superiorly,  by  the  external 
border  of  the  orbital  surface  of  the  superior  maxillary  bone  and  a  small  pari  of 
the  palate  bone  inferiorly;  by  a  small  part  of  the  malar  bone  externally;  and  it 
joins  the  pterygo-maxillary  fissure  at  right  angles  internally.  By  means  of 
this  fissure  the  orbit  communicates  with  the  temporal  fossa,  zygomatic  fossa, 
and  the  spheno-maxillary  fossa.  The  superior  maxillary  nerve  and  it >  orbital 
branch,  the  inferior  orbital  vessels,  and  the  ascending  branches  from  Meckel's 
ganglion   (spheno-palatine)   are  transmitted  by  this  fissure. 

The  pterygo-maxillary  fissure  passes  at  light  angles  from  the  inner  ex- 
tremity of  the  spheno-maxillary  fissure  and  is  therefore  vertical  in  direction. 

It  is  formed  by  the  separation  of  the  superior  maxillary  bone  from  the 
pterygoid  process  of  the  sphenoid  bone  and  is  shaped  like  the  letter  \  .  It 
transmits  the  branches  of  the  internal  maxillary  artery  and  connects  the  spheno- 
maxillary fossa  with  the  zygomatic  fossa. 

The  spheno-maxillary  fossa  is  situated  beneath  the  apex  of  the  orbit  where 
the  spheno-maxillary  fissure  joins  the  pterygo-maxillary  fissure.  It  is  bounded 
by  the  under  surface  of  the  body  of  the  sphenoid  bone  and  orbital  process  of 
the  palate  bone  superiorly,  by  the  superior  maxillary  bone  anteriorly,  by  the 
anterior  surface  of  the  base  of  the  pterygoid  process  and  lower  part  of  the  anter- 
ior surface  of  the  greater  wing  of  the  sphenoid  bone  posteriorly,  by  the  vertical 
plate  of  the  palate  internally.  The  sphenoidal  fissure,  the  spheno-maxillary 
fissure,  and  pterygo-maxillary  fissure  open  into  it.  The  orbital  fossa,  nasal 
fossa,  and  the  zygomatic  fossa,  and  the  cavity  of  the  cranium  communicate  with 
this  fossa.  The  foramen  rotundum  superiorly,  the  vidian  foramen  belo^  and 
internal  to  the  foramen  rotundum,  and  the  pterygopalatine  foramen  open  on 


556  ANATOMY  IN  A  NUTSHELL. 

its  posterior  wall.  The  spheno-palatine  foramen  and  the  foramen  of  the  pos- 
terior palatine  canal  open  on  its  inner  wall.  .Meckel's  ganglion,  the  superior 
maxillary  nerve,  and  the  termination  of  the  internal  maxillary  artery  are  in 
this  fossa. 


LESSON    CXCI. 
Female  Organs  of  Generation.     (Plates  CCLXXI-CCLXXII-CCLXXIII). 
The  internal  female  organs  of  generation  are,  (1 )  the  vagina,  (2)  the  uterus 

(3)  i lie  Fallopian  tubes,  (4)  the  ovaries,  while  the  external  female  organs  of 
generation  are  known  by  the  term  vulva  or  pudendum. 

The  vagina  is  the  sexual  canal  of  the  female  which  extends  upward  and 
slightly  backward  from  the  vulva  to  the  uterus.  Its  upper  extremity  embraces 
the  cervix  uteri,  the  posterior  wall  reaching  the  cervix  higher  up  than  does  the 
anterior  wall.  The  anterior  wall  is  two  ami  three-fourths  inches  long,  while 
the  posterior  wall  is  three  and  three-fourths  inches  long.  These  walls  are  in 
contact.  There  is  a  longitudinal  ridge  (carina)  of  the  mucous  membrane  on 
the  lower  half  of  the  anterior  wall,  while  on  the  posterior  wall  there  are  two 
ridges  called  cohnnme  rugarum.  From  all  three  of  these  ridges  transverse 
rugae  pass.  In  all  the  higher  mammalia  the  vagina  is  the  terminal  section  of  a 
Mnllerian  dud  or  oviduct  united  with  its  fellow,  while  in  the  lower  mammalia 
the  vagina  is  double,  wholely  or  in  part  there  being  two  more  or  less  complete 
vagina,  the  right  and  the  left.  In  some  oviparvus  animals,  as  birds,  the  termi- 
nation of  the  oviduct  beyond  the  uterine  part  receives  the  name  of  vagina. 

The  hymen  is  a  erescentric  or  circular  mucous  fold  which  constricts  the 
vagina  at  its  entrance.  When  the  hymen  is  ruptured  warty  eminences  mark 
its  -iic.  These  are  called  carunculae  myrtiformes.  The  hymen  has  the  fol- 
lowing forms: 

1.  Hymen  bifenestratus  (biforijB)is  one  in  which  there  are  two  openings 
side  by  side  and  a  broad  septum  between  them. 

2.  HYMEN  CRIBRIFORMIS  is  one  in  which  the  opening  is  filled  by  membrane 
pierced  by  many  small  openings. 

3.  HYMEN  DENTICULAR  is  one  in  which  the  opening  has  serrate  edges. 

4.  Hymen  imperforate  is  one  which  completely  closes  the  vaginal  orifice. 
In  this  condition  a  surgical  operation,  after  commencement  ofthe  menstrual 
period,  is  necessary. 

5.  Hy.mkn  si  i  i. i'ii  i;i.i>  is  one  having  an  irregularly  curved  edge  as  if 
carved  ou1   of  thickened  tissue. 

6.  Hymi  nsepti  sis s  in  which  the  opening  is  divided  by  a  narrow  septum. 

7.  1 1  "i  m  EN  SUBSEPT1  3  is  one  in  which  the  opening  is  partly  filled  by  a  septum 
growing  ou1  of  one  wall  bnt  not  reaching  the  other. 

Although  the  hymen  is  most  always  ruptured  by  sexual  congress  it  may 
remain   unbroken   until   parturition. 

The  vagina  is  smallest  below  and  largest  where  it  surrounds  the  os  uteri, 
where  it  is  very  dilatable. 

The  vagina  has  in  FRONT  ok  it  the  urethra  and  the  posterior  wall  of  the 
bladder,  BEHIND  it  the  anterior  wall  of  the  rectum  and  the  pouch  of  Douglas. 


AXATOMV    IX    A    NUTSHELL. 


.-).)< 


ox  each  side  of  it  are  the  Levator  aid  muscles  and  the  recto-vesical  fascia. 

The  vagina  has  three   coats: 

1.  Outer  or  fibro-elastic.     2.  Middle  or  muscular.     3.  Mucous  or  internal. 

The  circular  fibers  near  the  entrance  constitute  the  Sphincter  vagina  mus- 
cle which  has  been  described  on  page  493. 

The  mucous  lining  of  the  vagina  is  covered  with  squamous  laminated 
epithelium,  it  has  no  "lands  but  is  furnished  with  crypts  and  follicles, there- 
fore the  fluid  which  moisten-  it  is  the  nature  of  a  transudation  rather  than 
that  of  a  secretion. 

Nerve  Supply. — Hypogastric  plexus,  the  fourth  sacral,  and  the  pudic 
ei  ve. 

PLATE  CCLXXXIII. 

TERMINATION  OF  SEMICIRCULAR     CANALS 

CONNECTION  OF  MODIOLUS  WITH  CUPOLA 

APEX  OF    MODIOLUS 
FIRST      WINDING  OF     COCHLEA 

SECOND    WINDING  OF     COCHLEA 

SCALA  TYMPANI  INFERIOR 
THIRD     HALF     WINDING 
OF     COCHLEA 


BASE  OF  COCHLEA 

The  Boxy  Cochlea. 

Blood  Supply. — A  branch  of  the  internal  iliac  artery,  on  either  side. 
passing  to  the  vagina  and  base  of  the  bladder.  This  artery  corresponds  to  the 
inferior  vesical  artery  in  the  male.  It  also  receives  branches  of  the  uterine 
artery. 

Lymphatics  of  the  vagina  end  in  the  pelvic  inguinal  nodes. 


LESSON  CXCII. 

The  uterus  is  that  pari  of  the  female  sexual  passage  to  which  a  ripe  ovum 
is  conveyed  from  the  ovary  ami  in  which  it  is  detained  in  gestation  until  the 
fetus  is  matured  and  expelled  in  parturition.  The  non-pregnan1  human  uterus 
is  a  pear-shaped  organ  about  three  inches  long:  with  a  broad  flattened  part 
above  called  the  body  and  a  narrow,  more  cylindrical  pari  below  called  the  cer- 
vix. Within  is  a  cavity  which  passes  out  in  the  Fallopian  tube  on  each  side 
above  ami  below  opens  into  the  vagina.  The  cavity  narrows  as  it  passes  into 
the  cervix  at  the  internal  os  and  continues  downward  to  the  cervical  canal  to 
terminate  at  the  external  os  uteri  or  OS  tinea'.  The  uterus  i>  supported  by  the 
broad  ligament  which  is  a  transverse  fold  of  peritoneum  ami  embraces  it  on 
each  side.  It  has  accessory  ligaments,  such  as  the  round  ligament,  vesico- 
uterine ligament,  and  lecto-uterine  ligament.      It   consists  of  :i   serous  or  peri- 


ANATOMY  IN  A  NUTSHELL. 

toneal  coat,  a  middle  coat  of  smooth  muscular  fibers  forming  most  of  its  thick- 
ness, and  an  epithelial  lining. 

The  dimensions  of  the  uterus  are  as  follows:  about  three  inches  in  length. 
aboul  two  inches  in  breadth,  and  about  an  inch  in  thickness.     The  walls  of  the 
uterus  are  about  three-eighths  of  an  inch  in  thickness.     In  women  who  have 
borne  children  these  dimensions  are  increased. 
It    weighs   from   seven   to   twelve   drachm.-. 

The  direction  of  the  uterus  is  towards  the  umbilicus,  slightly  to  the  right 
ant  I  forms  an  angle  with  the  vagina  close  to  ninety  degrees,  and  as  a  rule  the 
left  superior  angle  is  a  little  further  forward  than  the  right.  The  position  of  the 
uterus  is  changed  when  the  bladder  is  full  or  when  the  rectum  is  full.  In  dis- 
eased conditions  it  may  be  axtkflexed  (an  abnormal  forward  curvature);  a 
form  of  displacement  in  which  the  upper  part  of  the  organ  is  bent  forward,  or 
we  may  have  ax  ANTEVERSION  (a  forward  tipping  or  tilting  of  the  organ);  a 
displacement  in  which  the  organ  is  tipped  forward  but  not  bent  at  an  angle  as 
anteflexion).  It  may  be  retroplexed  (bent  backward),  or  there  may  be  a 
retroversion  (the  tipping  of  the  entired  organ  backward). 

The  fundus  of  the  uterus  is  broad  and  convex  and  is  covered  with  peri- 
toneum. 

The  body  is  flat  anteriorly,  convex  posteriorly,  and  concave  laterally.  It 
is  joined  to  the  bladder  by  its  lower  anterior  fourth.  The  posterior  surface  of 
the  body  is  entirely  covered  with  peritoneum,  while  in  front  the  peritoneum 
covers  its   upper  three-fourths. 

The  cervix  is  the  lower  constricted  portion  and  is  embraced  by  the  upper 
extremity  of  the  vagina. 

The  cavity  of  the  body  is  triangular  and  flattened  from  before  backward. 
This  cavity  has  too  lateral  cornua  above,  and  a  constricted  opening   (internal 

■  its  lower  angle. 

The  cavity  of  the  cervix  is  spindle-shaped  ami  has  on  its  anterior  and  pos- 
terior walls  longitudinal  folds  called  arbor  vitse. 

The  external  os  is  a  transverse  orifice  at  the  lower  end  of  the  cavity  of  the 
cervix  and  opens  into  the  vagina.      It  has  an  anterior  lip  and  a  posterior  lip. 

'I'm.    LIGAMENTS   OF  THE    UTERUS   ARE    EIGHT   IX    NUMBER. 

1.  The  anterior  ligament  (vesico-uterine)  is  a  reflexion  of  the  peritoneum 
from  the  front  of  the  uterus  on  to  the  bladder. 

2.  The  posterior  ligament  (recto-uterine)  passes  from  the  posterior  wall  of 
the  uterus  and  over  the  upper  one-fourth  of  the  vagina  and  then  to  the  rectum 
and  sacrum,  thus  forming  the  pouch  of  Douglas  which  is  behind  the  upper 
portion  of  the  vagina. 

'■'>  and  1.  The  two  lateral  or  broad  ligaments  are  folds  of  peritoneum  which 
pass  From  the  sides  of  the  uterus  to  the  lateral  wall.-  of  the  pelvis,  and  thus  form 
:i  septum  across  the  pelvic  cavity.  The  broad  ligaments  contain  the  Fallopian 
tubes,  the  round  ligaments,  the  ovaries,  the  parovaria  (organs  of  Rosenmuller). 
blood  vessels  and  nerves,  as  well  as  connective  tissue  and  unstriped  muscle 
fibers. 

5  and  6.  The  two  sacro-uterine  ligaments  are  folds  of  peritoneum  which 


ANATOMY    IN    A    NUTSHELL.  *>">*» 

pass  from  the  sides  of  the  uterus  to  the  sides  of  therectum  first, then  to  the 

sacrum. 

7  and  8.  The  two  round  ligaments  arc  about  five  inches  Long  and  extend 
from  the  lateral  aspect  of  the  fundus  of  the  uterus  through  the  inguinal  canals 
to  the  labia  majora.  They  are  composed  of  muscular  tissue,  areolar  tissue, 
and  fibrous  tissue,  as  well  as  vessels  and  nerves. 

The  canal  of  Xuck  is  a  tubule  of  peritoneum  in  the  young  female  descending 
from  the  uterus  into  the  inguinal  canal.     It  is  usually  obliterated  in  the  adult. 

Blood  Supply. — (1)  The  uterine,  which  is  a  branch  of  the  anterior  division 
of  the  internal  iliac  artery.  (2)  funicular  from  the  superior  vesical,  (3)  the 
ovarian   from   the  abdominal   aorta. 

Nerve  Supply. — From  the  inferior  hypogastric  and  ovarian  plexus  of 
the  sympathetic,  and  the  third  and  fourth  sacral  nerves. 

The  lymphatics  of  the  cervix  end  in  the  pelvic  nodes,  while  those  from 
the  body  end  in  the  lumbar  node.-. 

The  coats  of  the  uterus  are  three,  (1)  a  serous,  (2)  a  muscular,  and  (3)  a 
mucous. 

The  serous  coat  is  the  peritoneum  which  invests  the  uterus,  except  at 
its  lower  anterior  one-fourth. 

The  muscular  coat,  which  is  composed  of  smooth  muscular  fiber  inter- 
mingled with  the  areolar  tissue,  blood  vessels  and  nerves,  forms  the  chief  bulk 
of  the  uterus.  The  circular  muscular  fibers  are  most  numerous  in  the  cervix, 
while  the  longitudinal  are  most  numerous  in  the  body  of  the  uterus. 

The  mucous  coat  is  very  thick  (one-eighth  of  an  inch)  is  closely  adherent 
to  the  internal  muscular  layer.  It  is  pale  and  smooth,  and  has  the  openings 
of  numerous  glands  upon  its  surface  and  is  covered  with  ciliated  columnar 
epithelium.  The  ovula  of  Naboth  are  glandules  or  follicles  within  the  os  uteri 
and  cervical  canal  which  are  often  distended  with  mucus,  which  mucus  Naboth 
mistook  for  human  ova.  hence  their  name. 

A  laceration  of  the  cervix  in  a  diathesis  or  neuropathic  constitution 
is  followed  (1)  by  irritation.  (2)  indigestion,  (3)  malnutrition.  (4)  anemia.  (5) 
neurosis. 


LESSON  CXCIII. 
The  Fallopian  tubes  (oviducts)  which  serve  to  convey  the  ovum  from  the 
ovary  to  the  uterine  cavity,  are  two  in  number.  Each  one  is  aboul  four  inches 
long  and  one  eighth  of  an  inch  in  diameter  and  they  are  situated  in  the  free  or 
upper  margin  of  the  broad  ligament,  extending  from  the  superior  angles  of  the 
uterus  to  the  superior  or  outer  extremity  of  the  ovary.  One  end  of  the  Fallopian 
tube  opens  into  the  uterus  at  its  superior  external  point .  and  the  other  end  opens 
into  the  peritoneal  cavity.  Each  tube  is  lined  with  ciliated  columnar  epithe- 
lium and  its  mucous  lining  is  continuous  with  the  uterine  mucous  membrane  at 
one  extremity  and  with  the  peritoneum  at  the  other  extremity.  The  meso- 
salpinx is  the  mesentery  of  the  fallopian  tube  and  it  is  that  part  of  the  broad 
ligament  between  the  tube  and  the  ovary.  Each  tube  increase-  in  size  from 
within  outward  and  consists  of  the  following  parts: 


560 


ANATOMY  IN  A  NUTSHELL. 


1.  The  isthmus  is  the  inner  constricted  third  of  the  tube  which  is  hard, 
cylindrical,  and  nearly  horizontal.  It  is  about  an  inch  and  a  half  long  and 
one-eighth  of  an  inch  in  diameter. 

2.  The  ampulla  (receptaculum  seminis)  is  the  outer  dilated  portion  curving 
over  the  ovary  and  extends  from  the  isthmus  to  the  fimbriated  extremity.  Its 
diameter  is  about  twice  that  of  the  isthmus  and  its  walls  are  thinner  and  softer. 
The  isthmus  and  the  ampulla  make  the  body  of  the  tube. 

3.  The  Iniundibulum  is  the  expanded  outer  end. the  opening  of  which  is 
the  ostium  abdominale. 

4.  The  fimbriae  are  fringe-like  processes  which  are  arranged  in  two  or  three 
concentric  circles.  The  frimbria  ovarica  is  larger  than  its  fellows  and  is  at- 
tached to  the  superior  extremity  of  the  ovary. 

5.  The  hydatid  of  Morgagni  is  the  cyst  like  remnant  of  the  Mullerian  duct 
attached  to  the  oviduct  by  a  long  stalk  of  peritoneum. 


PLATE  CCLXXXIV. 


TERMINATION  OF  SEMICIRCULAR     CANALb 

CONNECTION  OF  MODIOLUS  WITH  CUPOLA 
CUPOLA.  ^ 

APEX  OF    MODIOLUS 
CALA  VESTIBULI  c/^^J^S5^---^FIRST       WINDING  OF     COCHLEA 

SECOND    WINDING     OF    COCHLEA 
,B0NY  SPIRAL 
LAMINA 

—  THIRD     HALF 
SUP        WINDING      OF 
COCHLEA 
"  SCALA  TYMPANI     INFERIOR 

CENTRAI    CANAL  OF  MODIOLUS  BASE  OF  MOOIOLUS 

The  Boxy  Cochlea  Cut  Through. 


\eu\  e  Supply.— The  nerves  are  derived  from  a  plexus  around  the  uterine 
and  ovarian  arteries. 

Blood  Supply. — The  external  tubular  from  the  ovarian  ami  the  internal 
tubular  from  the  uterine. 

[/j  \irn  V.TICS,  after  joining  with  those  of  the  uterus,  empty  into  the  lumbar 

lioile-. 

The  ovaries,  which  are  the  essential  female  organs  of  generation,  are  two 

grayish  pink  bodies  situated  in  the  broad  ligament  behind  ami  below  the  Fallo- 
pian tube.  The  position  of  the  ovary  is  indicated  on  the  body  by  the  mid- 
point of  a  line  drawn  from  the  anterior  superior  spinous  process  of  the  ilium  to 
symphysis  pubis. 

The  dimensions  of  the  ovary  arc  one  and  a  half,  by  three-fourths,  by  one- 
third  of  an  inch.     They  are  not  so  dense  as  the  ^esticle  and  in  old  age  atrophiy. 

T  LIG  \  Ml. NTS    ok    'nil-:    OVARY     ARE: 

1.  The  utero-ovarian,  which  is  over  an  inch  in  length,  connects  the  inferior 
extremity  of  the  ovary  with  the  superior  angle  of  the  uterus.     This  ligament 


ANATOMY    IN    A    NUTSHELL.  561 

has  iii  it  fibrous  tissue,  plain  muscular  tissue  which  Ls  derived  from  the  super- 
ficial muscular  layer  of  the  uterus. 

2.  The  tubo-ovarian  (fimbria  ovarica)  joins  the  superior  extremity  of  the 
ovary  with  the  fimbriated  extremity  of  the  Fallopian  tube. 

3.  The  suspensory  (lumbo-ovarian)  is  the  upper  part  of  the  external  border 
of  the   broad   ligament. 

In  the  normal  position  of  the  ovary,  if  their  axes  were  continued,  they 
would  meet  in  front  of  the  uterus,  but  the  position  of  the  ovary  varies  because 
the  ligaments  are  attached  to  movable  points.  For  instance,  if  the  uterus 
turns  to  the  right  the  ovary  of  that  side  is  vertical  and  the  ovary  of  the  opposite 
side  is  nearlv  horizontal. 


LESSON   CXCIV. 

The  ovary  consists  of  a  vascular  stroma  which  contains  the  Graafian  foll- 
icles. 

The  stroma  is  composed  of  connective  tissue  which  has  hi  it  cells,  white 
fibrous  tissue,  yellow  elastic  tissue,  plain  muscular  fibers,  blood  vessels  and 
nerves.  From  the  hilum  a  core,  called  medullary  substance,  passes  into  the 
center  of  the  ovary.  It  is  composed  of  stroma  and  has  passing  from  it  numerous 
trabecular  to  the  cortex  of  the  ovary,  thus  leaving  spaces  in  which  are  situated 
Graafian  follicles.  The  tunica  albuginea  is  a  condensed  layer  of  the  stroma 
which  covers  the  ovary.  The  epithelial  covering  which  surrounds  the  tunica 
albuginea  is  the  remains  of  the  germinal  epithelium. 

The  Graafian  follicles  are  the  ova  sacs  which  contain  the  ova.  The  ma- 
jority of  these  Graafian  follicles  are  microscopic,  but  when  matured  they  lie- 
come  much  larger.  The  smallest  ones  vary  from  gi  to  i  of  an  inch  in 
diameter  and  the  largest  ones  from    i   to  *  of  an  inch  in  diameter. 

The  tunica  fibrosa  encloses  the  blood  trunks  and  lymphatic  spaces  of  the 
follicle.     This  is  the  outer  layer  of  the  follicle. 

The  tunica  propria  is  a  vascular  layer  composed  of  connective  tissue  cells 
and  capillar}'  plexuses.     This  is  the  inner  layer  of  the  follicle. 

The  membrana  granulosa  is  the  cell  layer  which  lines  the  inner  surface  of 
the   Graafian    follicle. 

The  discus  proligenis  is  that  part  of  the  membrana  granulosa  in  which  the 
Ovum  is  imbeded. 

The  membrana  propria  (vitalline  membrane)  is  between  the  membrana 
granulosa  and  the  tunica  propria. 

The  corpus  luteum  is  the  yellow  spot  in  the  substance  of  the  ovary  and  is 
caused  by  the  rupture  of  the  Graafian  follicle,  but  it  disappears  when  impreg- 
nation has  not  occurred.  When  impregnation  has  occurred  it  may  undergo 
remarkable  development . 

The  true  corpus  luteum  (corpus  luteum  of  pregnancy)  is  usually  regarded 
as  absolute  proof  of  previous  impregnation.  The  false  corpus  luteum  (corpus 
luteum  of  menstruation)  attains  its  greatesl  development  in  less  than  a  week 
and  begins  to  shrink  in  less  than  three  weeks  and  completely  disappears  in  a 


562  ANATOMY  IN  A  NUTSHELL. 

few  weeks.  The  true  corpus  luteum  continues  to  grow  for  two  or  three  months 
and  may  be  as  large  as  one-third  of  the  entire  ovar}\  It  continues  till  toward 
the  end  of  gestation  and  then  shrinks  to  a  small  white  scar  which  may  not  en- 
birely  disappear  until  a  month  after  labor.  While  this  is  the  general  rule  it 
does  not  always  hold  good  for  bodies  which  are  identical  with  the  true  cor- 
i'oi;\  i.itka  have  been  found  in  the  virgin  ovaries. 

The  ovary  in  its  descent  may  pass  into  the  inguinal  canal  and  out  the  ex- 
ternal abdominal  ring  and  become  an  external  organ  like  the  testicle.  This 
is  a  very  rare  occurrance.  At  the  third  month  of  intra-uterine  life  the  ovaries 
are  situated  in  the  lumbar  region  in  front  of  the  Psoas  magnus  near  the  kidney 
and  by  the  ninth  month  they  have  descended  to  the  brim  of  the  pelvis.  This 
is  caused  by  the  lumbar  region  growing  away  from  the  ovary. 

Nerve  Supply. — The  nerves  are  from  the  ovarian  plexus  of  the  sympa- 
thetic and  branches  of  the  third  and  fourth  sacral  nerves. 

Blood  Supply. — Ovarian  from  the  abdominal  aorta  which  corresponds  to 
the  spermatic  in  the  male.  The  blood  from  the  left  ovary  passes  through  its 
veins  into  the  left  renal  vein,  while  the  blood  from  the  right  ovary  passes  into 
the   inferior  vena   cava. 

Lymphatics  from  the  ovary  pass  into  the  lumbar  nodes. 


LESSON  CXCV. 

The  external  female  organs  of  generation  are  known  by  the  term  vulva  or 
pudendum  and  includes  (1)  the  mons  veneris,  (2)  the  labia  majora,  (3)  labia 
minora,  (4)  clitoris,  (5)  the  orifice  of  the  vagina. 

The  mons  veneris  (mount  of  Venus)  is  a  round  prominence  at  the  symphysis 
pubes  in  the  female,  which  is  cushioned  with  fat  and  covered  with  hair. 

The  labia  majora  are  hairy  folds  of  the  skin  on  either  side  of  the  slit  of  the 
vulva  extending  from  the  mons  veneris  to  the  perineum.  Where  they  meei 
anteriorly  they  form  the  anterior  commissure,  and  where  they  meet  below  they 
form  the  posterior  commissure  (fourchette)  which  is  about  an  inch  in  front  of 
the  anus  at  the  anterior  boundary  of  the  perineum.  The  fossa  navicularis  is 
between  the  posterior  commissure  and  the  hymen.  The  nerve  supply  of  the 
labia  majora  is  the  superficial  perineal  from  the  pudic  and  the  inferior  pudendal 
from  the  small  sciatic. 

The  labia  minora  (nymphae)  are  folds  of  mucous  membrane  within  the  labia 
majora.  They  extend  from  the  prepuce  of  the  clitoris  to  the  inner  surface 
of  the  labia  majora.  They  are  not  well  developed  until  the  age  of  puberty  and 
air  largesl  during  pregnancy.  The  vestibule  is  the  space  between  these  lips 
and   the  orifice  of  the  vagina. 

The  clitoris,  which  i>  situated  at  the  anterior  angle  of  the  vulva  is  a  small 
elongated  erectile  body  of  the  female  of  most  mammals.  These  mammals 
include  the  human  species  and  numerous  birds,  as  the  ostrich.  It  differs  from 
the  penis  of  the  male  in  that  it  is  smaller  and  as  a  rule  not  perforated  by  a  ure- 
thra, although  it  is  in  some  animals,  as  lemurs.  In  the  human  female  it  is 
usually  concealed   in   the  normal  state  of  the  parts,  but  in  the  spider-monkey 


ANATOMY    IN    A    NUTSHELL. 


563 


it  is  quite  large  and  it  is  difficult  to    distinguish  it  from  the  penis.       It  con- 
sists of  the  corpora  cavernosa  and  the  glans  clitoridis. 

The  stalk  hydatid  of  Morgagni,  when  present  in  the  female,  is  situated  in 
the  broad  ligament  at  the  outer  extremity  of  the  ovary.  Ii  is  a  small  peduncu- 
lated sac,  being  a  remnant  of  the  pronephros.  lis  homologue  in  the  male  is 
the  stalk  hydatid  of  Morgagni,  for  which  see,  Plate  CCLXXVI. 

The  preputium  clitoridis  is  a  fold,  formed  by  the  Labia  minora,  covering  the 
clitoris. 

The  duct  of  Gartner  (a  relic  of  the  Wolffian  duct)  is  a  straight  canal  ex- 
tending from  the  parovarium  through  the  broad  ligament  to  the  vagina. 

Bulbus  vestibuli  is  a  mass  of  erectile  tissue  situated  on  each  side  of  the  ves- 
tibule beneath  the  mucous  membrane.  It  is  homologous  to  the  bulb  of  the  cor- 
pus spongiosum  in  the  male,  while  the  pars  intermedialis  which  is  a  continua- 
tion of  the  bulbus  vestibuli  anteriorly  is  homologous  to  the  corpus  spongiosum 
itself. 

PLATE  CCLXXXV. 

COMMON  TERMINATION  OF  SUPERIOR  ANO 


AUDITORY  NERVE 


VESTIBULAR  NERVE 


COCHLEAR  NERVE 


POSTERIOR  SEMICIRCULAR  CANALS 


CUPOLA 


EXTERNAL ' 
SACCULARIS  R10"R  SEMICIRCULAR  CANAL 

BORDER  OF    SPIRAL    PLATE  AMPULLA    SUPERIOR 


The  Interior  of  the  Labyrinth  with  Distribution  of  Auihtoky  Nehye. 

The  paroophoron  (parovarium)  (organ  of  Etosenmuller)  is  a  relic  in  the 
broad  ligament  of  the  urinary  portion  of  the  Wolffian  body.  Ii  is  a  tubular  body 
homologous  to  the  organ  ofGiraldes  (Paradidymis) in  the  male.  It  is  present 
only  in  childhood  and  cannot  always  be  recognized. 

The  long  tube  of  the  parovarium  is  homologous  to  the  tubeof  the  epididymis. 

The  short  tubules  of  the  parovarium  are  homologous  to  therete  testis  and 
the  coni  vasculosi  in  the  male. 

Bartholin's  glands  are  the  vulvo-vaginal  glands  which  are  situated  on  each 
side  of  the  vagina  posteriorly  to  the  bulbi  vestibuli.  They  are  small  racemose 
glands  about  one-third  of  an  inch  Long  and  each  opens  with  a  due!  near  the 
nymphse.  Cowper's  glands  are  the  homologues  of  Bartholin's  glands.  Sec 
page  473,     For  description  of  the  female  urethra  see  page  17  1. 

The  Mammahv  Gland.     I  Plate  CCLXXIX). 


The  mammary  glands  are  named  is  zoology,  from  their  position,  axillary, 


564  ANATOMY    IN    A    NUTSHELL. 

pectoral,  ventral  or  abdominal,  and  inguinal.  Sometimes  they  are  quite  high 
on  the  sides  of  the  animal  but  are  never  dorsal.  The  mamma  of  the  cow  is 
situated  in  the  median  line,  being  formed  from  the  coalescence  of  as  many 
mammae  as  there  arc  teats.  These  glands  are  paired  as  arule  and  common  to 
both  sexes,  but  remain  rudimentary  and  functionless  in  the  male  as  a  general 
thing.     The  male  mammas  have  been  known  to  secrete  milk. 

The  mammary  gland  of  the  human  female  is  situated  between  the  third 
and  sixth  rib  on  each  side  between  the  sternum  and  the  axilla.  The  nipple 
is  situated  between  the  fourth  and  fifth  rib  about  four  and  one-half  inches  from 
the  middle  line  of  the  sternum ;  but.  of  course,  this  position  varies  .  The  base  of 
each  nipple  is  surrounded  by  a  zone  of  colored  skin  called  the  areola,  and  this 
areola  has  numerous  small  whittish  tubercles  which  contain  the  openings  of 
the  sebaceous  glands.  The  nipple  is  highly  vascular  and  its  skin  is  sensitive 
and  contains  retiform  tissue  and  unstriped  muscular  fibers.  There  are  about 
twenty  orifices  in  the  summit  of  the  nipple  which  are  the  ends  of  the  milk  ducts. 
This  gland  is  racemose  and  consists  of  from  fifteen  to  twenty  lobes,  which  are 
independent  of  one  another.  Each  of  these  lobes  is  made  up  of  lobules,  and 
these  are  formed  by  the  aggregation  of  alveoli  in  which  the  milk  is  secreted. 

Blood  Supply. — The  anterior  intercostals,  the  external  mammary  (long 
thoracic),    and  acromio-thoracic   arteries. 

Nerve  Supply. — Anterior  and  lateral  cutaneous  branches  of  the  inter- 
costal  nerves. 

Lymphatics  of  the  mammary  gland  pass  into  the  axillary  nodes. 

The  Wolffian  body  is  the  mesonephros  or  primitive  kidney,  the  excretory 
organ  of  the  embryo.  It  consists  of  a  long  tube  in  the  lower  part  of  the  body- 
cavity,  running  parallel  with  the  spinal  axis  and  joined  at  right  angles  by  a 
row  of  twisting  tubes  given  off  from  the  Malpighian  body,  and  forming  a  struc- 
ture resembling  a  comet.  The  Wolffian  body  develops  into  the  head  of  the 
epididymis,  vas  deferens,  and  ejaculatory  duct  in  the  male. 


LESSON  CXCVI 

The  Male  Organs  of  Generation.     (Plates  CCLXXIV-CCLXXV-CCLXXVI- 

CCLXXVII-CCLXXVIII). 

The  prostate  gland  is  shaped  like  a  chestnut  and  is  about  one  and  one-half 
inches  in  itsl  ransverse  diameter  while  it  is  one  and  one-fourth  inches  from  base 
to  apex.  Its  weight  is  aboul  the  same  as  the  testicle,  (six  drachms).  The 
\i'i.\  of  this  gland  is  a1  the  triagular  ligament,  [ts  base  is  at  the  neck  of  the 
bladder.  Its  posterior  surface  is  joined  to  the  rectum  by  areolar  tissue.  It 
-  dense  firm  capsule  which  is  derived  from  the  recto-vesical  fascia  and  the 
posterior  layer  of  the  trangular  ligament.    It  consists  of  a  median  lobe  and  two 

lateral  lobes.     It  is  c posed  of  glandular  matter,  and  muscular  fibers   which 

encircle   the   urethra. 


ANATOMY    IN    A    NUTSHELL.  565 

The  penis  is  composed  of  a  mass  of  erectile  tissue  enclosed  in  three  rod-like 
segments  which  are  firmly  united  together  by  a  sheath  composed  of  integu- 
ment, dartos,  and  fascia.  These  segments  arc  the  two  corpora  cavernosa,  and 
the  corpus  spongiosum.  The  root  of  the  penis  is  attached  to  the  symphysis 
and  pudic  arch.  The  body,  which  is  triangular  on  cross  section,  forms  the 
greater  part  of  the  free  portion  of  the  organ.  The  glans  forms  the  expanded 
distal  extremity  of  the  organ  and  is  more  developed  on  the  dorsal  than  on  the 
ventral  aspect,  and  the  urethral  opening  is  at  its  distal  extremity.  The  glans 
is  separated  from  the  body  by  a  constriction  called  the  neck. 

The  corpora  cavernosa,  which  lie  side  by  side,  form  the  upper  and  lateral 
parts  of  the  penis.  (Plate  CCLXXIV).  The  crura  are  formed  by  the  posterior 
one-fourth  of  the  corpora  cavernosa,  Plate  CCLXXV,  and  are  attached  to  the 
tuberosities  of  the  ischia  and  the  descending  rami  of  the  ischia.  The  groove 
above  the  corpora  cavernosa  are  for  the  dorsal  vessels  and  dorsal  nerves,  while 
the  groove  below  that  is  for  the  corpus  spongiosum.  The  suspensory  ligament 
of  the  penis  Is  a  fibrous  membrane  which  connects  the  root  of  the  organ  to  the 
symphysis  pubes.  The  fibrous  septum  between  the  two  corpora  cavernosa, 
only  present  between  its  posterior  two-thirds,  is  called  septum  pectiniform. 

The  corpus  spongiosum  lies  in  the  groove  between  the  corpora  cavernosa 
inferiorly.  This  has  no  erectile  tissue  in  it  like  the  corpora  cavernosa.  It  con- 
sists of  glans,  a  body,  and  a  bulb.  The  clans  is  somewhat  heart-shaped  and 
at  its  base  is  a  ridgecalled  corona  glandis,  behind  which  is  the  neck  of  the  penis. 
The  external  urinary  meatus  is  a  vertical  fissure  about  one-third  of  an  inch 
in  length  at  the  apex  of  the  glans.  It  is  the  outlet  of  the  urethra.  The  body 
of  the  corpus  spongiosum  has  passing  through  its  whole  length  the  urethra. 
For  description  of  the  urethra  see  page  472,  and  for  Plate  page  533.  The 
bulb  of  the  corpus  spongiosum  is  surrounded  by  the  Accelerator  mime  mus- 
cle. It  passes  posteriorly  to  within  an  inch  of  the  anus.  The  prepuce  is  a 
continuation  of  the  integument  of  the  penis  which  more  or  less  completely 
conceals  the  glans.  The  fr.enum  pr.eputium  is  a  fold  of  mucous  membrane 
which  connects  the  prepuce  with  the  glans  along  the  raphe.  Phimosis  (muz- 
zling or  closure)  is  the  tightness  of  the  foreskin  such  that  it  cannot  be  drawn 
back  from  over  the  glans.  Paraphimosis  is  a  retraction  of  a  narrow  or  in- 
flamed foreskin  which  cannol  be  replaced.  Epispadias  is  a  congenital  defed 
in  which  the  urethra  opens  on  the  dorsum  of  the  penis.  In  female  epispadias 
there  is  a  fissure  of  the  upper  wall  of  the  female  urethra.  Bypospadias  i-  :i 
congenital  opening  of  the  urethra  on  the  under  side  of  the  penis.  In  the  female 
hypospadias  there  Is  an  opening  of  the  urethra  in  the  vagina. 

The  dartos  is  the  reddish,  cellular,  contractile  tissue  beneath  the  skin  of 
the  penis  and  continuous  with  the  dartos  tissue  of  the  scrotum.  The  female 
dartos  is  a  layer  of  unstriped  muscular  fibers  immediately  under  the  skin  o\ 
the  labia  majora.  The  dartos  enter-  into  the  formation  of  the  prepuce,  and 
some  authorities  claim,  forms  a  kind  of  a  sphincter  around  the  preputial  ori- 
fice. The  areolar  tissue  of  the  penis,  which  contains  the  superficial  vessels  and 
nerves,  is  just  beneath  the  dartos.  (Plate  CCLXXIV).  The  deep  fascia  of  the 
penis  is  beneath  the  areolar  tissue.     It   is  joined  to  the  skin  and  the  corpus 


566 


ANATOMY    IN    A    NUTSHELL. 


spongiosum.  This  fascia  and  the  dartos  aided  by  the  Bulbo  cavernosi  and  the 
[schio-cavernosi  muscles  compress  the  veins  of  the  penis  in  the  action  of  erec- 
tion. 

Blood  Supply.— The  arteries  to  the  penis  are  branches  of  the  internal 
pudic.  (a)  The  artery  of  the  bulb,  which  goes  to  the  bulb  of  the  corpus  spon- 
giosum, (hi  the  arteries  of  the  corpora  cavernosa,  (c)  the  dorsal  artery  of  the 
penis.  The  envelops  of  the  penis  are  supplied  by  the  external  pudic,  the 
superficial  perineal,  and  the  dorsal  artery.  The  veins  of  the  penis  are  in  two 
sets,  (a)  superficial  veins,  which  pass  between  the  dartos  and  fascial  sheath 
end  in  the  long  saphenous  and  femoral  veins,  (b)  the  deep  veins,  which  drain 
the  corpora  cavernosa,  corpus  spongiosum,  end  in  the  deep  dorsal  vein  and  in 
the  internal  pudic  vein. 

Lymphatics  of  the  penis  are  divided  into  two  sets,  (a)  superficial  ones 
which  pass  to  the  inguinal  nodes,  and  (b)  deep  ones  which  empty  into  the  pelvic 
and  Lumbar  nodes  as  well  as  in  the  inguinal  nodes. 

Nerve  Supply. — The  genital  branch  of  the  genito-crural  and  the  super- 
ficial perineal  branches  of  the  pudic  supply  the  covering  of  the  penis,  while  the 
dorsal  nerve  of  the  penis,  and  superficial  perineal,  and  hypogastric  plexus  sup- 
ply the  erectile  bodies. 


PLATE  CCLXXXVI. 


SEMICIRCULAR  CANAL 


5CALA  TYMPANI      INFERIOR 

Interior  of  Bony  Labyrinth. 


The  spermatic  cord  is  about  four  inches  long  and  extends  from  the  internal 
abdominal  ring  to  the  globus  minor  of  the  epididymis.  It  passes  through  the 
inguinal  canal.  It  is  composed  of  the  following  structures  held  together  by 
areolar  tissue  and  invested  by  layers  broughl  down  by  the  descent  of  the  testicle. 

1.  The  vas  deferens,  which  is  the  excretory  duct  of  the  testicle  passing 
from  the  testis  to  the  ejaculatory  dud.  It  is  recognizable  by  its  cord-like 
resistance  to  pressure. 

_'.  The  artery  of  the  vas  deferens,  which  is  a  branch  of  the  superior  vesical 
artery.  It  arises  from  this  artery  near  the  place  where  the  vas  deferens  crosses 
the  obliterated  hypogastric  artery,  and  it  divides  into  an  ascending  branch 
which  follows  the  vas  deferens  through  the  inguinal  canal,  and  a  descending- 
branch  which  passes  n>  the  dilated  poll  ion  of  the  vas  deferens  and  the  vesicula 
seminalis. 

:!.  The  cremasteric  artery,  which  is  a  branch  of  the  dee])  epigastric,  passes 


ANATOMY  IN  A  NUTSHELL.  567 

through  the  inguinal  canal  with  the  vas  deferens  andsupplies  the  Cremasteric 
muscle. 

4.  The  spermatic  artery,  which  is  a  branch  of  the  abdominal  aorta,  passes 
over  the  Psoas  muscle  to  the  internal  abdominal  ring,  then  through  the  inguinal 
canal  into  the  scrotum  to  the  testicle.  It  gives  off  the  following  branches, 
(a)  ureteral  branchesto  theureter,  (b)  cremasteric  branches  to  the  Cremasteric 
muscle,  (c)  epididymal  to  the  epididymis,  (d)  testicular  branches  to  the  bpdy 
of  the  testis. 

5.  The  spermatic  veins,  or  pampiniform  plexus,  surrounds  the  artery. 

(i.  Spermatic  plexus  of  nerves  (sympathetic)  accompanying  the  artery. 

7.  The  vas  aberrans  is  a  blind  tube  connected  with  the  epididymis  or  vas 
deferens.     Its  homologue  is  the  duct  of  Gartner  in  the  female. 

8.  The  lymphatics  which  pass  with  the  veins. 

9.  The  Internal  cremasteric  muscle,  which  is  composed  of  smooth  muscu- 
lar fibers. 

10.  The  obliterated  processes  vaginalis  of  the  peritoneum,  which  is  a  relic 
of  the  tube  between  the  tunica  vaginalis  and  the  peritoneum. 

11.  A  branch  of  the  ilio-inguinal  nerve. 

12.  A  branch  of  the  ffenito-crural  nerve. 


LESSON  CXCVII. 

The  infundibuliform  fascia  which  is  from  the  transversalis  fascia,  the 
cremasteric  fascia  which  is  from  tin1  Internal  oblique  muscle,  the  intercolumnar 
fascia  which  is  from  the  external  spermatic  fascia,  the  superficial  fascia  and  the 
skin  of  the  scrotum,  all  these  are  coverings  of  the  spermatic  cord  from  within 
outward. 

The  vesicula?  seminales  are  two  lobulated  membranous  pouches  between 
the  base  of  the  bladder  and  the  rectum,  and  they  serve  as  reservoirs  for  the 
semen,  as  well  as  secrete  the  fluid  which  is  added  to  the  semen.  They  have 
three  coats,  an  external  or  fibrous  coat,  a  middle1  or  muscular  coat,  and  an  in- 
ternal or  mucous  coat. 

The  ejacnlatory  duct  is  about  an  inch  long  and  is  formed  by  the  union  of 
the  vas  deferens  and  the  vesicula  seminalis.  Its  diameter  is  aboul  one-eighth 
of  an  inch  above,  but  where  it  opens  it  is  about  one-fill ieth  of  an  inch.  1 1  opens 
on  the  verti  montanum  on  either  side  of  the  opening  of  the  sinus  pocularis. 

The  testicles  are  two  in  number  and  aresuspended  by  the  spermatic  cords. 
They  weigh  less  than  an  ounce  and  are  about  an  inch  and  a  half  long,  and  inch 
and  a  quarter  deep,  and  about  an  inch  in  thickness.  They  secrete  the  seminal 
fluid.     They  have  the  following  coverings  from  within  outward. 

1.  The  tunica  vaginalis,  which  is  ;i  serous  covering  formed  by  ;i  portion  of 
the  peritoneum  which  descended  with  the  testicle  and  afterwards  forms  a  closed 
pouch  investing  it.  This  tunica  consists  of  two  layers,  a  visceral  ami  :i  parietal 
layer.  Beneath  the  tunica  vaginalis  is  the  tunica  albuginea  which  i^  ;i  strong 
fibrous  coat  (Plate  CCLXXVII) ;  and  beneath  this  coat,  the  tunica  vasculosa 
(pia  mater  testis)  which  is  composed  chiefly  of  blood  vessels  held  together  by 


568  ANATOMY  IX  A  NUTSHELL. 

areolar  tissue.  This  coat  lines  the  tunica  albuginea  and  the  various  septa 
within  the  testicle. 

2.  The  infundibuliform  fascia  (internal  spermatic)  is  the  fascia  propria 
and  is  a  continuation  downward  of  the  transversalis  fascia. 

:;.  The  cremasteric  fascia  (middle  spermatic  fascia)  is  composed  of  mus- 
cular fibers  (the  ('remaster  muscle)  which  are  derived  from  the  lower  border 
of  the  Internal  oblique  muscle. 

4.  The  intercolunmar  fascia  (external  spermatic)  which  is  closely  adherent 
to  the  dartos. 

5.  The  scrotum  consists  of  two  layers,  (a)  the  integument  which  is  more 
or  less  pigmented  and  covered  in  the  adult  with  scattered  hair.  A  raphe  is 
present  in  the  median  line  from  which  pass  transverse  wrinkles,  (b)  The  dartos 
which  is  a  reddish,  cellular,  contractile  tissue  beneath  the  skin  of  the  scrotum. 

1.  The  epididymis  (upon  the  testis)  lies  at  the  posterior  and  superior  part 
of  the  testicle  and  consists  of  the  globus  minor  which  contains  the  efferent 
duct,  and  the  globus  major  composed  of  vasa  efferentia  and  coni  vasculosa. 
If  the  epididymis  were  unraveled  it  would  be  a  tube  twenty  feet  long. 

The  lobules  of  the  testicle  are  contained  in  the  spaces  formed  by  the  tra- 
becular which  divide  the  testicle  into  divisions.  These  lobules  consist  of  the 
tubuli  seminiferi  which  consist  of  a  basement  membrane  lined  with  a  layer  of 
cuboidal  cells  in  which  are  developed  the  spermatoza.  The  tubuli  at  the  apices 
of  the  lobules  become  straight  and  join  the  vasa  reta  which  join  the  rete  testes 
in  the  mediastinum,  the  rete  testes  end  in  the  vasa  efferentia  which  per- 
forate the  tunica  albuginea  and  form  the  coni  vasculosa. 

Gubernaculum  testis  is  a  fetal  cord  attached  to  the  lower  end  of  the  epidi- 
dymis and  to  the  bottom  of  the  scrotum.  It  governs  the  descent  of  the  testicle. 
Its  homologue  is  the  round  ligament  of  the  female. 

The  paradidymis  (organ  of  Giraldes)  is  on  the  spermatic  cord  above  the 
epididymis.  It  represents  the  remains  of  the  posterior  part  of  the  Wolffian 
body,     h  is  a  closed  tube.     Its  homologue  is  the  paroophoron  in  the  female. 

The  duct  of  Kathke  is  a  part  of  the  duct  of  Muller  which  persists  hi  post- 
natal life  and  remains  patulous.  The  oviduct  is  the  homologue  of  the  dud  of 
Rathke. 

The  sessile  hydatid  of  Morgagni  is  the  upper  part  of  the  duct  of  Muller, 
which  persists  and  is  attached  to  the  upper  aspect  of  the  testicle.  The  fimbria 
of  the  oviduct  is  the  homologue  of  the  sessile  hydatid  of  Morgagni. 

LESSON   CXCVIII. 

The  Organs  oi    Hearing.     (Plates  CCLXXX-CCLXXX VII, inclusive). 
These  organs  consist  of  three  portions. 

1.  The  external  ear,  which  consists  of  (a)  pinna  or  auricle  which  is  not  of 
much  importance  physiologically,  and  (b)  the  meatus  auditorius  externus, 
which  is  ;i  canal  leading  inward  to  the  tympanic  membrane. 

2.  The  middle  ear,  which  is  composed  of  (a)  the  tympanum  (an  air  chamber) 
containing  the  malleus,  incus,  and  stapes  (the  auditory  ossicles  )  and  com- 


ANATOMY    IN    A    NUTSHELL. 


569 


municates  with  the  naso-pharynx  by  means  of  the  Eustachian  tube,  (b)  the 
mastoid  antrum,  (c)  the  mastoid  cells,  (b)  and  (c)  are  accessory  air  chambers 
to   the   tympanum. 

3.  The  internal  ear  or  labyrinth,  contains  the  membranous  labyrinth 
which  is  a  cast  of  the  bony  structures.  The  membranous  labyrinth  contains 
the  endolymph,  and  within  it  are  the  specialized  neuro-epithelial  cells  and  the 
terminations  of  the  auditory  nerve.  The  perilymph  is  on  the  outside  of  the 
membranous  labyrinth. 

The  External  Ear. 

The  pinna  is  the  projecting  part  of  the  ear  lying  outside  of  the  head,  and  is 
attached  to  the  malar  and  temporal  bones  by  ligaments.  It  consists  of  a  layer 
of  yellow  fibro-cartilage  covered  with  integument.     It  has  the  following  parts. 

PLATE  CCLXXXVII. 


FOSSA    FOR    INCUS 


ARTICULAR    SURFACE     FOR     MALLEUS 


LEFT  MALLEUS 


SHORT        PROCESS 


ANTERIOR  CRU3 


BASE- 


POSTERIOR  CRUS 


HEAD  OF  MALLtUS 

SHORT  PROCESS 
—  SLENDER  PROCESS 

HANDLE  OR  MANUBRIUM 


BASE    OF    STAPES 

Malleus,  [ncus  and  Stapes. 

1.  The  helix  is  the  outer  curved  edge  of  the  pinna  which  passes  upward 
from  the  rim  of  the  pinna  and  ends  behind  in  the  lobule. 

2.  The  lobule  is  the  lowest  portion  of  the  auricle  and  consists  of  fatty  and 
areolar  tissue. 

3.  The  fossa  of  the  helix  (scaphoid  ibssa)  is  a  depression  internal  to  the 
helix. 

4.  The  antihelix  is  a  range  which  begins  above  the  Lobule  .-u  the  anti- 
tragus  and  passing  upward  bifurcates  to  enclose  a  triangular  depression  called 
the  fossa  of  the  antihelix. 


570  ANATOMY  IN  A  NUTSHELL. 

5.  The  concha  is  the  deep  hollow  in  the  center  of  the  pinna  which  leads 
into  the  auditory  canal. 

6.  The  tragus  is  a  conical  eminence  in  front  of  the  concha  projecting  back- 
ward over  the  orifice  of  the  external  auditory  meatus.  It  is  usually  covered 
with  hair  along  its  inferior  border. 

7.  The  antitragus  is  a  small  projection  posterior  to  the  tragus  from  which 
it  is  separated  by  a  deep  fissure  called  the  incisura  intertragica. 

The  muscles  of  the  external  ear  are  divided  into  two  sets,  the  extkixsk 
ami  the  entrinsh  .    The  extrinsic  aie.  the  Attrahens  aurem,  Retrahens  aurem, 
and  Attollens  aurem.     These  muscles  have  been  described  on  page  522  and  in 
the  table  of  muscles  in  the  back  of  the  book. 

The  [ntrinsic  muscles  are: 

1.  Tragicus,  which  lies  vertically  on  the  outer  surface  of  the  tragus. 

L'.  Antitragicus  lies  on  the  posterior  wall  of  the  auditory  canal.  It  arise- 
from  the  outer  part  of  the  antitragus  and  passes  upward  to  be  inserted  into 
the   posterior  extremity  of  the  helix. 

3.  Helicis  minor  is  often  absent,  but  when  present  is  attached  to  the  com- 
mencemenl  of  the  helix  and  extends  into  the  concha. 

4.  Helicis  major  is  situated  on  the  anterior  margin  of  the  helix. 

">.  Transversus  aurem  is  situated  on  the  posterior  surface  of  the  auricle 
in  the  depression  between  the  helix  and  the  convexity  of  the  concha. 

6.  Obllquus  aurem  is  on  the  posterior  surface  of  the  auricle  passing  upward 
from  the  convexity  of  the  concha. 

Nerve  Supply. — From  the  auriculo-temporai,  auricularis  magnus,  occipi- 
lalis  minor,  and  Arnold's  nerve  from  the  tenth.  The  intrinsic  muscles  receive 
the  seventh    nerve. 

Action  of  the  Intrinsic  muscles  is  to  retard  the  passage  of  sound  to  the 
meatus.     These  muscles  are  rudimentary  and  unimportant. 

Blood  Supply. — The  pinna  receives  the  posterior  auricular,  the  occipital. 
and  superficial  temporal  arteries. 

Lymphatics  of  the  pinna  empty  into  the  preauricular  nodes,  and  into  the 
nodes  upon  the  insertion  of  the  Sterno-cleido-mastoid  muscle. 

Tin'  external  auditory  canal  is  a  little  over  an  inch  long,  extending  from 
the  concha  to  the  membrana  tympani.  This  canal  is  curved  with  its  convexity 
upward.  This  canal  is  lined  with  integument  which  contains  sebaceous  and 
ceruminous  glands  and  also  numerous  hair  follicles. 

The  outer  one-third  of  this  canal  is  cartilaginous,  and  the  inner  portion 
osseous. 

The  Annulus  tympanicus  isthe  osseous  portions  of  this  canal  at  birth,  at 
which  time  it  is  an  incomplete  bony  ring. 

Blood  Supply.-  From  branches  of  the  internal  maxillary,  posterior  auri- 
cular, and  superficial   temporal. 

Nerve  Supply.  Auriculo-temporai,  auricularis  magnus.  and  Arnold's 
nerve. 

Tin  LYMPHATICS  of  the  external  auditory  meatus  end  in  the  parotid  and 
the  posterior  auricular  nodes. 


ANATOMY    IN    A    NUTSHELL.  571 

The  membrana  tympani,  which  is  attached  to  a  grooved  ridge  of  bone  at 

the  bottom  of  the  external  auditory  meatus,  is  an  oval,  clastic  semi-trans- 
parent membrane  about  7,]0  of  an  inch  in  thickness,  aboul  ,-'•.,  of  an  inch 
in  its  antero-posterior  diameter  and  slightly  less  in  its  vertical  diameter.  This 
membrane  is  situated  obliquely,  its  outer  surface  being  directed  outward, 
downward,  and  forward,  so  as  to  form  almost  a  continuation  of  the  posterior 

wall  of  the  external  auditory  meatus.     In  infancy  this  membrane  is  al >t 

horizontal.  The  membrana  tympani  is  composed  of  three  Layers;  an  outer 
or  cutaneous  layer,  a  middle  or  fibrous  layer,  and  an  inner  or  mucous  layer.  It 
has  the  following  points  for  consideration: 

1.  The  umbo  (naval)  is  the  dark  depressed  center  of  the  membrane. 

2.  The  cone  of  light  is  a  triangular  area,  the  apex  of  which  i>  attached  to 
the  tip  of  the  handle  of  the  malleus,  and  at  its  base  extends  toward  the  circum- 
ference of  the  membrane.  This  is  of  value  hi  diagnosis  of  diseases  of  the  tym- 
panum and  membrana  tympani. 

3.  The  tubercle  which  is  at  the  upper  border  is  formed  by  theshorl  pro- 
cess of  the  malleus. 

4.  The  stripe  which  runs  down  from  the  tubercle  to  the  umbo  and  is  formei  1 
by  the  handle  of  the  malleus. 

5.  Sharpnell's  membrane  (membrana  fiaccida)  is  situated  at  the  upper 
part  of  the  membrane  below  the  notch  of  Rivini.  This  notch  is  formed  where 
the  bony  ring  to  which  the  tympanic  membrane  is  attached  is  incomplete. 

6.  Rivinian  foramen  is  a  minute  opening  which  exists  in  Sharpnell's  mem- 
brane. 

7.  Membrana  tensa  is  all  the  tympanic  membrane  except  the  membrana 
fiaccida.     This  membrane  is  concave  externally. 

Blood  Supply. — From  tympanic  branches  of  the  internal  maxillary  and 
carotid  arteries. 

Nerve  Supply. — The  external  surface  receives  the  auriculo-temporal  from 
the  fifth  nerve  and  Arnolds'  nerve  from  the  tenth.  The  internal  surface  receives 
branches  from  the  tympanic  plexus. 


LESSON    CXCIX. 
The  Middle  Ear. 

The  tympanum  (drum)  is  an  irregular  cavity  situated  within  the  petrous 
portion  of  the  temporal  bone,  and  lined  with  mucous  membrane.  It  lies  be- 
tween  the  external  auditory  meatus  and  the  internal  ear.  lis  antero-posterior 
length  is  about  half  of  an  inch,  vertically  a  lil  tie  more  I  ban  half  an  inch,  and  its 
width  is  about  one  sixth  of  an  inch.  It  consists  of  two  main  parts,  (a)  attic  or 
recessus  epitympaniticus  which  is  situated  in  the  highesl  portion  of  the  tym- 
panic cavity  and  contains  the  head  of  themalleus  and  the  greaterparl  of  the 
incus.  This  attic  leads  into  the  mastoid  antrum,  do  Atrium  (tympanic. cav- 
ity proper)  is  situated  opposite  the  tympanic  membrane. 

The  roof  of  the  tympanum  is  a  thin  plate  of  bone  (tegmen  tympani)  which 
separates  the  tympanum  from  the  middle  fossa  :it  the  base  of  the  skull. 


PLATE  CCLXXXVII] 


ENCYSrtO       HERNIA 


INFANTILE       HERNIA 


HERNIA.      'NTC      THE     TUNICA       VAGINALIS 


HERNIA       INTO    THE    FUNICULAR    PROCESS 


Forms  of  Congenital  Hernia  (After  Deaver.) 
572 


ANATOMY    IN    A    NUTSHELL.  573 

The  floor  of  the  tympanum  is  formed  by  the  thin  plate  of  bone  which  sepa- 
rates the  tympanum  from  the  jugular  fossa. 

The  anterior  Avail  of  the  tympanum  is  deficient  above  where  the  Eustachian 
tube  opens  into  it.  This  wall  separates  the  tympanum  from  the  carotid  canal 
and  has  opening  of  canal  for  Tensor  tympani  muscle  above,  and  below  the  open- 
ing of  the  Eustachian  tube.  These  canals  are  separated  from  one  another  by 
the  processus  cochleariformis. 

The  posterior  wall  of  the  tympanum  separates  the  tympanum  from  the  mas- 
toid cells  and  communicates  wtih  the  mastoid  antrum  by  one  large  and  several 
small  openings. 

The  outer  wall  of  the  tympanum  is  formed  by  the  membrana  tympani  and 
by  the  squamous  portion  of  the  temporal  bone  above.  It  has  the  following 
points  for  consideration: 

1.  The  iter  chordae  postertus,  which  is  close  to  the  posterior  edge  of 
the  drum  head.  The  chorda  tympani  nerve  which  is  a  branch  of  the  seventh 
cranial  nerve  enters  the  tympanum  through  this  opening. 

2.  The  iter  chordae  anterius,  which  is  just  above  the  drum  head, 
is  the  opening  by  which  the  chorda  tympani  nerves  leaves  the  tympanum. 

3.  The  Glaseriax  fissure,  which  opens  above  and  in  front  of  the  head, 
lodges  the  long  process  of  the  malleus,  the  Laxator  tympani  muscle. and  the 
tympanic  branch  of  the  internal  maxillary  artery. 

The  inner  wall  of  the  tympanum  is  the  outer  wall  of  the  labyrinth  and 
presents  several  points  for  consideration. 

1.  The  fenestra  ovalis  leads  to  the  vestibule  and  is  closed  by  a  mem- 
brane which  is  attached  to  the  base  of  the  stapes. 

2.  The  fenestra  rotunda  is  below  the  fenestra  ovalis  and  leads  into 
the  scala  tympani  of  the  cochlea.  It  is  closed  by  the  membrana  tympani  secund- 
daria . 

3.  The  promontary  is  an  elevation  formed  by  the  first  turn  of  the  cochlea. 
It  is  covered  by  the  tympanic  plexus  and  is  located  between  the  two  fenestras 
and  in  front  of  them. 

-i.  The  pyramid  is  behind  the  fenestra  ovalis  and  from  its  summit  passes 
the  tendon  of  the  Stapedius  muscle,  and  a  branch  of  the  seventh  nerve  pierces 
the  pyramid  to  supply  the  Stapedius. 

5.  The  ridge  of  the  aqueductus  Eallopii.  which  is  above  the  fenestra 
ovalis  and  covers  the  seventh  nerve  in  its  passage  through  the  tympanum. 

Blood  Supply. — Tympanic  branch  of  the  internal  maxillary  artery,  tym- 
panic branch  of  internal  carotid  artery,  stylo-mastoid  branch  of  the  posterior 
auricular  artery,  petrosal  branch  of  the  middle  meningeal  artery,  a  branch 
of  ascending  pharyngeal  artery  which  enters  through  the  Eustachian  tube,  tym- 
panic branch  of  vidian  artery.  The  veins  of  the  middle  ear  follow  the  corres- 
ponding arteries  and  empty  into  the  temporo-maxillary  vein,  the  superior  petros- 
al sinus,  the  lateral  sinus,  the  internal  jugular  vein  and  pharyngeal  veins. 

The  lymphatics  of  the  middle  ear  end  in  the  posterior  auricular  and  caro- 
tid nodes. 

Nerve  Supply. — Tympanic  plexus  which  supplies  the  mucous  membrane 


.J74  ANATOMY    IN    A    NUTSHELL 

of  the  tympanum  and  is  formed  by  the  following  nerves:  (1)  Jacob-son's 
nerve,  (2)  great  superficial  petrosal  nerve,  (3)  small  superficial  petrosal  nerve, 
I  I  small  deep  petrosal. 

The  middle  ear  or  tympanum  is  filled  with  air  and  contains  the  malleus, 
incus  and  stapes.  These  form  a  chain  of  bones  which  transmits  the  impulses  of 
sound  waves  between  the  tympanic  membrane  and  the  parilymphand  endo- 
lymph  of  the  internal  ear. 

The  malleus  (hammer)  consists  of  the  following  parts,  (1)  a  head,  (2)  a  neck, 
(3)  :i  shorl  process,  (4)  long  process  (process  gracilis)  (5)  handle  (manubrim). 
The  handle  is  connected  with  the  middle  layer  of  the  drum  head  and  is  situated 
between  this  middle  and  mucous  layer.  The  short  process  (process  brevis) 
is  attached  to  the  Tensor  tympani  muscle.  The  long  process  is  received  into 
the  Glaseriarj  fissure.  The  head,  which  is  situated  in  the  attic,  is  connected 
with  the  roof  of  the  attic  by  the  superior  ligament  of  the  malleus  and  it  articu- 
lates with  the  body  of  the  incus. 

The  Incus  (anvil)  has  the  following  parts,  (1)  a  body  (head),  (2)  a  long 
process,  (3)  a  short  process.  The  body  articulates  with  the  head  of  the  malleus. 
This  joint  is  covered  by  a  capsular  ligament  and  lined  by  synovial  membrane. 
'I Tie  shorl  process  articulates  with  the  fossa  incudis  in  the  attic  to  which  it  is 
connected  by  fibrous  tissue.  The  long  process  articulates  with  the  head  of  the 
-tapes.  The  end  of  this  process  is  called  os  orbiculare.  This  os  orbiculare  is 
the  smallest  bone  in  the  body.     In  adult  life  it  forms  part  of  the  incus. 

The  stapes  (stirrup)  has  the  following  parts,  (1)  a  head,  (2)  a  neck,  (3)  a 
base  (foot  piece),  (4)  two  crura  (branches).  The  head  articulates  with  the  os 
orbiculare  of  the  incus.     This  is  a  ball-and-socket  joint. 

The  base  fits  on  the  membrane  closing  the  fenestra  ovalis.  The  neck  re- 
ceives the  tendon  of  the  Stapedius. 

The  Ligaments  of  the  malleus,  incus,  and  stapes  are  five  besides  the  capsular 
ligaments  of  their  articulations. 

1.  The  superior  ligament  of  the  MALLEUsisa  fibrous  band  passing  from 
the  head  of  the  malleus  to  the  outer  part  of  the  roof  of  the  attic. 

•_'.  Tin:  interior  ligament  of  the  malleus  is  attached  to  the  anterior 
wall  of  the  tympanum  and  to  the  anterior  part  of  the  head  and  neck  of  the 
malleus.      It   is  sometimes  described  as  the  Laxator  tympani  muscle. 

:;.  Tiii':  external  ligament  of  the  malleus  is  attached  to  the  neck  of 
the  malleus  by  its  apex  and  to  the  margin  of  notch  of  Rivini  by  its  base. 

1.  The  [NTERNAL  ligament  of  the  malleus  extends  from  the  tip  of  the 
processus  cochleariformis  to  the  insertion  of  the  Tensor  tympani  tendon. 

5.  The  ligament  of  the  incus  is  attached  to  the  short  process  of  the 
incus  and  to  the  posterior  wall  of  the  attic  near  the  orifice  of  the  mastoid  ant  urn. 

Besides  these  five  ligaments  just  named  we  have  capsular  ligaments  around 
the  joints  between  the  malleus  and  incus,  and  between  the  incus  and  stapes. 

The  muscles  of  the  tympanum  have  been  described  on  page  523. 

The  mastoid  antrum  is  situated  posterior  to  the  tympanum  and  is  lined 
with  mucous  membrane.  It  opens  in  the  attic  of  the  tympanum  and  into  the 
mastoid    cells. 


PLATE  CCLXXXIX. 


The  Lymph  ltic  Max. 
575 


576  ANATOMY  IX  A  NUTSHELL. 

The  mastoid  cells  are  no1  present  at  birth  but  at  the  age  of  puberty  there 
are  a  few  and  they  occupy  the  greater  portion  of  the  mastoid  process.  They 
are  secondary  organs  of  hearing. 

The  Eustachian  tube  is  a  passage  from  the  uaso-pharynx  to  the  tympanum. 
It  passes  inward,  downward,  and  forward  from  the  tympanum.  It  is  between 
an  inch  and  a  half  and  two  inches  long  and  from  one-twelfth  to  one-fifth  of  an 
inch  in  diameter.  It  is  made  up  of  a  bony  part  which  is  smaller  than  the  car- 
tilaginous  portion  and  situated  in  the  temporal  bone,  and  of  a  cartilaginous 
portion  which  is  somewhat  trumpet-shaped  ending  hi  the  pharynx.  Its  pur- 
pose is  to  equalize  the  air  pressure  within  the  tympanum  with  that  of  the  ex- 
ternal car.  At  the  point  where  the  bony  portion  joins  the  cartilaginous  portion 
i«  the  isthmus  tuba-.     The  opening  of  the  Eustachian  tube  into  the  tympanum 

PLATE  CCXC. 


A  Lymphatic  Node  (After  Gerrish.) 

is  on  the  anterior  wall,  while  its  pharyngeal  opening  is  on  the  lateral  wall  of 
the  naso-pharynx  behind  the  posterior  nares.     This  tube  is  closed  except  dur 
ing  swallowing,  when  it  is  opened  by  the  following  muscles:     Tensor  palati 
Levator  palati.  Salpingo-pharyngeus,  and  pari  of  the  Palato-pharyngeus. 


lessox  re. 

The  Internal  Lai;.     (Labyrinth). 
This  car  consists  of  a  bony   labyrinth   within   which  is  the   membranous 
labyrinth. 

Tin'  bony  labyrinth  is  made  up  of  the  vestibule,  the  cochlea,  and  the 

SEMK  li;<  i  LAB    CAN  ^LS. 

The  membranous  labyrinth  is  smaller  than  the  bony  labyrinth  of  which  it 
is  a  casl  and  the  space  between  the  two  is  lined  with  endothelium  which  con- 
tain- parilymph.  The  parts  which  make  the  membranous  labyrinth  are,  the 
rjTRK  i.i  which  is  a  membranous  sac  in  the  vestibule,  saccule  which  is  also  a 
membranous  sac  in  the  vestibule,  membranous  semicirculab  canals  which 
are  in  'he  osseous  canals,  and  the  membranous  cochlea  which  is  aspiral  tube 
inclosed  in  the  osseous  cochlea. 


ANATOMY    IN  A    NUTSHELL.  577 

The  eighth  nerve  (auditory)  which  is  the  portio  mollis  of  the  seventh  nerve. 
This  nerve  has  no  neurilemma. 

The  organ  of  Corti  is  the  terminal  auditory  apparatus  in  the  membranous 
cochlea. 

The  internal  auditory  meatus  is  the  opening  into  the  internal  oar  from  the 
cranial  cavity  for  the  seventh  ami  eighth  nerve  and  stylo-mastoid  artery. 

The  vestibule  is  an  oval  cavity  at  the  entrance  to  the  cochlea  within  the 
internal  car.  Vertically  it  is  about  one-fifth  of  an  inch,  laterally  about  one- 
tenth  of  an  inch.  It  contains  a  fluid  called  perilymph  and  the  utricle  and 
saccule,  and  membranous  labyrinth.  It  is  situated  between  the  cochlea  and 
the  semicircular  canals  internal  to  the  tympanum.  It  has  the  following  points 
for  consideration: 

1.  The  fenestra  ovalis  is  on  its  outer  or  lateral  wall  and communicantes 
with  the  tympanum.  It  is  closed  by  the  base  of  the  stapes  and  its  annular 
ligament  which  is  from  the  periosteal  lining  of  the  vestibule. 

2.  The  fovea  hemispherica  is  a  small  circular  depression  at  the  inner 
portion  of  the  inner  or  median  wall  at  the  bottom  of  which  are  numerous  mall 
openings  for  the  vestibular  branch  of  the  auditory  nerve. 

-    3.  The  crista  vestibuli  is  posterior  to  the  fovea  hemispherica.     It  is  a 
vertical  crest. 

The  fovea  cochlearis  is  a  small  depression  which  is  perforated  for  the 
passage  of  the  filaments  of  the  auditory  nerve. 

5.  The  aqueductus  vestibuli  is  on  the  posterior  portion  of  the  inner  wall. 
It  transmits  a  small  vein  and  lodges  the  ductus  endolymphaticus  which  con- 
nects the  membranous  labyrinth  with  the  general  cerebral  lymph  spaces. 

6.  The  fovea  he.mielliptica  is  an  oval  fossa  on  the  roof. 

In  the  posterior  portion  of  the  vestibule  are  the  five  openings  of  the  semi- 
circular canals,  while  at  the  anterior  portion  of  the  vestibule  is  an  opening 
leading  into  the  scala  vestibuli  of  the  cochlea. 

The  semicircular  canals  are  three  C-shaped  bony  tubes  aboul  one-twentieth 
of  an  inch  in  diameter  which  are  situated  above  and  behind  the  vestibule. 

1.  The  superior  SEMICIRCULAR  canal  is  nearly  an  inch  long  and  lies  in  a 
saggital  plane  of  the  body. 

2.  The  external  semicircular  canal  is  abut  one-fifth  of  an  inch  long 
and  lies  horizontally. 

3.  The  posterior  semicircular  canal  is  nearly  an  inch  long  and  lie-  in  a 
coronal  plane.  From  this  we  can  see  that  the  three  semicircular  canal-  are  at 
right  angles  to  one  another  and  each  forms  more  than  a  semicircle.  The  ampulla 
is  about  one-tenth  of  an  inch  in  diameter. 

The  cochlea  is  a  bony  tube  about  one  and  a  half  inch  long  situated  anteriorly 
to  the  vestibule.  It  resembles  a  snail  shell  and  coils  around  a  central  axis  two 
and  three-fourths  times.     It  has  the  following  points  for  consideration  : 

1.  The  modiolus  (central  axis)  around  which  is  wound  a  spiral  tube. 
This  axis  has  numerous  canals  in  it  for  branches  of  the  auditory  nerve  and 
artery,  the  largest  one  of  these  canals  is  canalis  centralis  modioli. 

2.  The  base  of  the  cochlea  is  two-fifths  of  an  inch  in  diameter  and  i- 


578  ANATOMY    IN    A    NUTSHELL. 

perforated  by  numerous  foramina  for  branches  of  the  auditory  nerve.     It  is 
directed  toward  the  meatus  auditorius  interims. 

3.  The  spiral  canal  (canalis  spiralis  modioli)  is  the  space  between  the 
modiolus  and  the  outer  wall  of  the  cochlea.  It  diminishes  in  diameter  as  it 
approaches  the  apex  of  the  cochlea  and  ends  in  a  closed  extremity  (cupola) 
after  making  two  and  three-fourths  turns. 

4.  The  lamina  spiralis  is  a  thin  osseous  plate  projecting  into  the  spiral 
canal  from  the  modiolus  reaching  half  way  across  the  spiral  canal.  It  winds 
around  the  modiolus  and  ends  near  the  apex  in  a  hook-like  process  (the  ham- 
ulus). Helicotrema  is  the  deficiency  in  the  last  half  turn  of  the  cochlea.  The 
membrana  basilaris  and  the  membrana  Reissner  are  two  membranes  which 
extend  from  the  free  border  of  the  lamina  spiralis  and  are  connected  with  the 
outer  wall  of  the  cochlea.  Between  them  is  the  scala  media  (cochlear  duct). 
The  scala  media  divides  the  spiral  canal  into  three  parts,  the  scala  tympani 
below  and  the  scala  vestibuli  above,  and  between  these  two  the  scala  media. 
The  scala  tympani  opens  into  the  tympanum  at  the  fenestra  rotunda,  however, 
this  opening  is  closed  by  the  membrana  secundaria.  The  scala  vestibuli  opens 
into  the  vestibule.  Where  these  two  scalse  communicate  with  each  other  at 
the  summit  of  the  cochlea  is  called  the  helicotrema. 

The  membranous  labyrinth  is  situated  within  the  bony  labyrinth  from 
which  ii  is  separated  by  the  perilymph. 

The  utricle  lies  partly  in  the  fovea  hemielliptica  and  is  a  flattened,  oblong 
sac.  h  is  filled  with  endolymph  and  communicates  with  the  saccule  through 
a  small  tube  in  the  aqueductus  vestibuli.  The  membranous  semicircular  canals 
open  into  the  utricle  by  five  orifices. 

1.  Macula  acustica  utricularis  is  a  thickened  portion  of  the  walls  of  the 
utricle  which  contain  calcareous  masses  (otoliths)  in  which  are  distributed 
filaments  of  the  vestibular  branch  of  the  auditory  nerve. 

2.  DUCTUS  ENDOLYMPHATICUS  which  has  been  previously  described. 

The  saccule,  which  is  smaller  than  the  utricle,  receives  branches  of  the 
auditory  nerve  through  the  openings  in  the  fovea  hemispheriea,  and  these 
branches  end  in  the  thicked  part  of  the  wall  which  is  covered  with  otoliths. 

The  membranous  semicircular  canals  are  the  same  shape  as  the  osseous 
semicircular  canals  and  are  about  one-fourth  the  diameter  of  the  osseous  canals. 
Their  enlarged  extremities  are  called  ampulla. 

The  membranous  cochlea  (cochlear  duct)  (scala  media)  is  a  spiral  tube 
enclosed  in  the  spiral  canal  of  the  osseous  cochlea  between  the  scala  vestibuli 
and  the  scala  tympani.  It  is  filled  with  endolymph  and  contains  the  organ 
ol  Cortl  which  is  a  complex  arrangement  of  modified  epithelial  cells  including 
the  rods  of  Corti  and  the  auditory  cells. 

Blood  Supply.— From  the  auditory  artery  which  enters  the  internal 
auditory  meati  -  and  divides  into  branches  for  the  cochlea  and  vestibule.  The 
veins  empty  into  the  internal  jugular  and  into  the  superior  petrosal  sinus. 

Nerve  Supply.-  The  auditory  ne  ve  which  is  the  nerve  of  special  sense  of 
hearing. 


ANATOMY  IN  A  NUTSHELL.  579 

Lymphatics  of  the  internal  ear  end  in  the  tympanic  and  intracranial 
lymphatic  vessels. 

The  superficial  mesial  origin  of  the  auditory  nerve  is  from  the  groove  be- 
tween the  olivary  and  restiform  bodies  at  the  lower  border  of  the  pons. 

The  deep  mesial  origin  is  in  the  dorsal  auditory  nucleus,  which  is  on  the 
outer  side  of  the  inferior  fovea  on  the  floor  of  the  fourth  ventricle 

The  superficial  lateral  origin  of  the  auditory  nerve  is  from  the  auditory 
striae,  and  after  winding  around  the  upper  end  of  the  restiform  body  joins  the 
mesial  root  in  the  groove  between  the  olivary  and  restiform  bodies. 

The  deep  lateral  origin  is  from  (1)  a  ganglion  of  the  lateral  root,  which  is 
situated  in  this  root  as  it  winds  around  the  restiform  body,  (2)  the  auditory 
striae,  (3)  the  trapezium  of  the  pons,  (4)  the  ventral  auditory  nucleus.  This 
last  nucleus  lies  in  front  of  the  restiform  body  between  the  two  roots. 

The  main  trunk  of  the  auditory  nerve  now  passes  into  the  internal  auditory 
meatus  with  the  facial  nerve  and  the  auditory  artery.  At  the  bottom  of  this 
meatus  it  comes  to  the  lamina  cribrosa,  where  it  divides  into  the  cochlear  branch 
and  the  vestibular  branch.     (Plate  CCXXI). 

The  cochlear  branch  sends  branches  to  the  saccule,  to  the  ampulla  of  the 
posterior  semicircular  canal,  and  to  the  hair  cells  of  the  organ  of  Corti  in  the 
membranous  cochlea. 

The  vestibular  branch  has  upon  it  the  ganglion  of  Scarpa,while  in  the  internal 
auditory  meatus  it  sends  branches  to  the  utricle,  to  the  ampulla  of  the  external 
semicircular  canal,  to  the  ampulla  of  the  posterior  semicircular  canal. 

The  principal  salivary  glands  are  the  parotid,  submaxillary,  and 
sublingual. 

The  parotid  gland  takes  its  name  from  its  position  which  is  near  the  ear. 
It  is  about  the  size  of  the  pinna  (auricle)  of  the  external  ear,  and  weighs  almost 
an  ounce.  It  extends  from  the  mastoid  process  and  the  angle  of  the  jaw  BE- 
LOW to  the  zygoma  above,  being  immediately  in  front  of  the  external  meatus. 
This  gland  is  saddled  over  the  ramus  of  the  lower  jaw, and  lias  upon  its  outer 
surface  a  few  lymphatic  nodes,  while  its  inner  surface  has  two  processes  upon 
it.  One  of  which  extends  behind  the  styloid  process  of  the  temporal  bone  and 
beneath  the  mastoid  process  of  the  same  bone,  while  the  other  is  in  front  of  the 
styloid  process.  The  following  structures  pass  through  the  parotid  gland:  (1) 
the  external  carotid  artery  which  gives  off  the  temporal  branch  above,  the 
posterior  auricular  behind,  and  the  internal  maxillary  internally,  also  the  trans- 
verse facial  artery  which  is  a  Iranch  of  the  temporal  passes  through  the  upper 
part  of  the  "land,  (2)  the  common  trunk  formed  by  the  temporal  and  internal 
maxillary  veins,  (3)  a  branch  connecting  this  trunk  with  the  internal  jugular 
rein,  (4)  the  facial  nerve  and  its  branches.  (.">)  branches  of  the  greal  auricular 
nerve. 

The  upper  anterior  portion  of  the  gland  is  called  socia  parotidis.  This 
portion  is  often  detached  from  the  rest  of  the  gland. 

The  duct  of  this  gland  is  about  two  and  one-half  inches  long.  It  is  called 
Stenson's    or   Steno's    duct.      After   crossing    the    Masseter    muscle    and    passing 

into  tin1  substance  of  the  Buccinator  muscle  this  duct  opens  upon  the  inner  sur- 


580  ANATOMY  IN  A  NUTSHELL. 

face  of  the  cheek  by  a  small  opening  opposite  the  second  malar  tooth  of  the  upper 
jaw.  This  duct  is  about  the  size  of  a  crow-quill.  It  has  an  external  or  fibrous 
coat,  which  contains  contractile  fibers,  and  an  internal  or  mucous  coat,  which 
is  lined  with  short  columnar  epithelium. 

Blood  Supply. — From  branches  of  the  external  carotid  artery. 

Nerve  Supply. — (1)  sympathetic  from  the  carotid  artery,  (2)  the  fifth 
nerve  (auriculo-temporal),  (3)  the  seventh  nerve,  (4)  the  great  auricular  (cer- 
vical   plexus). 

The  submaxillary  gland  which  weighs  about  two  drachms  is  situated  in 
the  anterior  part  of  the  submaxillary  triangle  of  the  neck  below  the  mylo- 
hyoid ridge  of  the  inferior  maxillary  bone.  The  stylo-maxillary  ligament  sep- 
arates this  gland  from  the  parotid  gland,  and  the  Mylo-hyoid  muscle  separates 
it  from  the  sublingual  gland. 

TIh'  duct  of  this  gland  (Whadon's)  is  about  two  inches  long  ami  opens  at 
the  side  of  the  frsenum  linguae. 

Blood  Supply. — From  the  facial  and  lingual  arteries. 

Nerve  Supply. — (1)  sympathetic,  (2)  the  fifth  nerve  (submaxillary),  (3) 
the  seventh  nerve  (chorda  tympani). 

The  sublingual  gland  weighs  about  a  drachm  and  is  situated  at  the  side  of 
the  frsenum  lingua?  in  a  fossa  above  the  mylo-hyoid  ridge  of  the  lower  jaw  close 
to  the  symphysis. 

The  duct  of  this  gland  is  called  the  Bartholin  or  Rivinus. 

This  duct  opens  into  the  duct  of  the  submaxillary  gland  near  its  termi 
nation. 

Blood  Supply. — From  the  sublingual  and  submental  arteries. 

Nerve  Supply. — (1)  Sympathetic,  (2)  the  fifth  (gustatory). 


ANATOMY  IN  A  NUTSHELL.  "sl 


ATABLE    OF    MUSCLES 

WITH 

Nerve  Supply  and  Page  of  Description. 


Cranial  Region. 

Occipito-frontalis. — Facial,    or    branches    of    third    cranial    nerve,    the 

occipital  part  sometimes  receives  the  occipitalis  minor  nerve Page  513 

Auricular  Region. 

Attollens  aurem. — 

Origin. — From  the  Occipito-frontalis  aponeurosis. 

Insertion. — Into  the  pinna  of  ear  above.     (Plate  XIV.) 

Action. — It  raises  the  pinna. 

Nerve  Supply. — Facial. 

Blood  Supply. — Temporal  arteries. 

Attrahens  aurem. — 

Origin. — From  the  cranial  aponeurosis. 

Insertion. — Into  the  helix  of  the  ear  anteriorly. 

Action. — It  draws  the  pinna  forward. 

Nerve  Supply.— Facial. 

Blood  Supply. — Branches  from  the  temporal. 

Retrahens  aurem. — Posterior  auricular  of  facial  nerve Page  522 

Palpebral  Region. 

Orbicularis  palpebrarum. — Temporal  branch  of  facial  or  fibers  of  third 
cranial  nerve Page  508 

Corrugator  supercilii. — Temporal  branch  of  facial  or  fibers  of  third 
cranial  nerve Page  508 

Tensor  tarsi. — Facial  and  perhaps  third  cranial  nerve Page  532 

Orbital  Region. 

Levator  palpebr^e. — Third  cranial  nerve Page  529 

Rectus  superior. — Third  cranial  nerve Page  530 

Rectus    inferior. — Third    cranial    nerve Page  530 

Rectus  internus. — Third  cranial  nerve Page  53  1 

Rectus  externus. — Sixth  cranial  nerve Page  ■">:'>  1 

Obliquus  superior. — Fourth  cranial   nerve Page  ■">•"■•> 

Obliques  inferior. — Third  cranial  nerve Page  538 

Muscles  of  Tympanum. 

Stapedius. — Tympanic  branch  from  seventh  cranial  nerve Page  523 

Tensoi;  tymi'wi.     From  the  otic  ganglion Page  523 

Laxator  tympani Page  531 

Nasal    Region. 

Ptramidalis  nasi. — 


ANATOMY  IN  A  NUTSHELL. 

Origin. — From  the  Occipito-frontalis. 

[nsertion. — Into  the  fibro-cartilage  of  the  ala  of  the  nose  with  the  Com- 
■  'i-  nasi. 

Action.  Depresses  the  eye  brows  and  makes  the  transverse  wrinkles  on 
the  bridge  of  the  nose. 

N  u;\  i.  Supply.—  Facial. 
I '.ij ><>i>  Supply.— Facial. 

Levator   labij   buperioris  al^bque  nasi. — Facial Page  539 

Dilatob  naris   posterior. — Facial Page  540 

DlLATOB     NARIS    ANTERIOR. — 

Origin.— From   the  alar  cartilage. 

Insertion. — Into  the  skin  near  the  margin  of  the  nose. 

Action.— To  dilate  the  nostril. 

\'i.k\  i:  Supply.— Facial. 

Blood  Supply. — Facial. 

Compressor   nasi. — Facial Page  539 

Compressor   narium  .minor. — 

Origin.— From   the   fibro-cartilage  of  the  nose. 

Insertion. — Into  the  skin  at  the  end  of  nose. 

Action.  -  To  dilate  the  nostril. 

Nerve  Supply. — Facial. 

Blood  Supply. — Facial. 

Depressor    al.k  nasi. — Facial Page  539 

Superior  Maxillary  Region. 

Levator    labii     superioris. — Facial Page  534 

Levator  anguli  oris. — Facial Page  539 

Zygom  \th  is  major. — Facial Page  535 

Zygomaticus  minor. — Facial Page  535 

Inferior  Maxillary  Region. 

I.i.\  vim;    LABI)    tNFERiORis. — Facial Page  545 

Depressor    labii    inferioris.. — Facial Page  544 

Depressor    anguli    oris. — Facial Page  545 

Intermaxillary  Region. 

l'.i  (i  [NATOR.  Facial  and  buccal  branch  of  inferior  maxillary  division  of 
fifth  crania]   aerve Page  540 

Risorius. — 

<  >i;h,i \.     From  the  masseter  fasica. 

Insertion.     Into  the  angle  of  the  mouth. 

Action.— To  draw  the  angle  of  the  mouth  backward. 

N i.i;\  i.  Si  pply.     Facial. 

Blood  Supply.     Facial. 

Orbicularis   oris.-  Facial    through    its   buccal   and   supramaxillary   di- 

visions Page  540 

Temporo-Maxillary  Region. 

TEMPORAL.-    Inferior  maxillary  division  of  the  fifth  nerve Page  508 

Masseter.     Inferior  maxillary  division  of  the  fifth  nerve Page  520 


ANATOMY    IN    A    NUTSHELL.  583 

Pterygo-Maxillary  Region. 

Pterygoideus  externus.—  Pterygoid   branch   of  the   Inferior   maxillary 

division  of  the  fifth  nerve Page  529 

Pterygoideus   internus. — Pterygoid    branch    of    the    Inferior   maxillary 

division  of  the  fifth  nerve Page  529 

Superficial  Cervical  Region. 

Platysma  myoides. — Facial Page  5  15 

Sterno-cleido-mastoid. — Spinal  accessory,  second   and   third   (?)   cervi- 
cal nerves Page     l" 

Infra-Hyoid  Region. 
(Depressors  of  the  Os  hyoides  and  the  Larynx). 
Sterno-hyoid. — Branches  from  the  loop  of  communication  between  the 

cervical  plexus  and  twelfth  cranial  nerve Page    40 

Sterno-thyroid. — Branches  from  the  loop  of  communication    between 

the  cervical  plexus  and  twelfth  cranial  nerve Page    41 

Thyro-hyoid. — Hypoglossal  nerve Page  550 

Omo-hyoid. — Tenth,  twelfth,  and  cervical  plexus Page    59 

Supra-Hyoid  Region. 
(Elevators  of  the  Os  hyoides  and  the  larynx.) 
Digastric. — Posterior  belly  gets  the  facial,  and  the  anterior  belly  gets 

mylo-hyoid  branch  of  inferior  dental  nerve Page  521 

Stylo-hyoid. — Facial Page  522 

Mylo-hyoid. — Mylo-hyoid  branch  of  inferior  dental  of  fifth  nerve  Page  5  I  1 

Geniohyoid. — Hypoglossal  nerve Page  5  1 1 

Lingual  Region. 
(Muscles  of  the  Tongue.) 

Genio-hyo-glossus. — Hypoglossal  nerve Page  5  I  I 

Hyo-glossus. — Hypoglossal  nerve Page  551 

Stylo-GLOSSUS. — Hypoglossal  nerve Page  522 

Chondro-glossus. — Hypoglossal     nerve Page  550 

Inferior  lingualis. — Hypoglossal  nerve Page  551 

Superior  lingualis  lies  near  the  upper  surface  of  the  tongue  passing 

from  base  to  apex.      Its  action  is  to  shorten   the  tongue  and   make  ii   concave 

longitudinally. 

Nerve   Supply.—  Hypoglossal. 

Blood  Supply. — Same  as  tongue. 

Transverse  lingualis  runs  from  the  median  raphe  of  the  tongue  to  the 

dorsum  and  margin.     Its  action  is  to  increase  the  length  of  the  tongue,  at  the 

same    time    make    it    narrow. 

X  kkye    Sui'i'M  .      I  lypoglossal. 

Blood  Supply.-  Same  as  tongue. 

Vertical  lingualis  consists  of  fasciculi  which  pass  from  the  dorsum  ol 

the   tongue  to    its   under  surface.      Its   action    is    to    make    the    tongue    Ik'it    and 
broad. 

Nerve   Supply.—  Hypoglossal. 

Blood  Supply. — Same  as   tongue. 


584  anatomy  in  a  nutshell. 

Palatoglossus. — 

Origin. — From  the  median  line  of  the  soft  palate  and  from  its  fellow  of 
the  opposite  side. 

Insertion. — Into  the  side  and  dorsum  of  the  tongue. 

Action.—  It  constricts  the  fauces  and  elevates  the  tongue,  also  pulls  down 
the  velum. 

Nerve  Supply. — Internal  branch  of  spinal  accessory  through  the  pharyn- 
geal plexus. 

Blood  Supply. — 

Muscles  of  the  Pharynx. 

Constrictor  inferior. — 

Origin. — From  the  cricoid  and  thyroid  cartilages. 

Insertion.— Into  the  fibrous  raphe  of  the  pharynx. 

Action. — It  compresses  the  pharynx  and  lifts  it  upward  and  backward. 

Nerve  Supply. — Pharyngeal  plexus  and  inferior  laryngeal. 

Blood  Supply. — Same  as  pharynx  which  is  given  on  page  315. 

Constrictor   medius. — Pharyngeal  plexus Page  551 

Constrictor  superior. — Branches  from  the  pharyngeal  plexus.  .Page  515 

Stylo-pharyngeus. — Glosso-pharyngeal Page  522 

Palato-pharyngeus. — 

Origin. — From  the  soft  palate  by  two  heads  near  the  median  line. 

Insertion. — Into  the  side  of  the  pharynx  and  posterior  border  of  thyroid 
cartilage.     It  joins   the   Stylo-pharyngeus   muscle. 

Action. — Constricts  the  fauces  and  elevates  the  larynx  and  tongue,  and 
closes  the  posterior  nares. 

Nerve  Supply.- — Internal  branch  of  spinal  accessory  through  the  pharyn- 
geal   plexus. 

Blood   Supply. — Same   as   pharynx.     Page   315. 
Muscles  of  the  Soft  Palate. 

Levator  palati. — Spinal  accessory  through  pharyngeal  plexus,  possibly 
facial  through  petrosal  branch  of  the  vidian  nerve Page  523. 

Tensor  palati. — From  the  otic  ganglion Page  523 

Azygos  uvuljE. — Spinal  accessory  through  pharyngeal  plexus.  .Page  549 

Palato-glossus,  which  has  been  described  with  the  muscles  of  the  tongue 
in    the   lingual    region. 

Palato-pharyngeus,  which  has  been  described  with  the  muscles  of  the 
pharynx. 

Muscles  of  the  Anterior  Vertebral  Region. 

Rectus  capitis  anticus  major. — First  cervical  and  loop  between  it  and 
second  cervical  nerve Page  514 

Rectus  capitis  antic  is  minor. — First  cervical  and  loop  between  it  and 
second  cervical  nerve Page  514 

Rectus   CAPITIS  lateralis. — First   cervical   and  a  loop  between  it  and 
second  cervical  nerve Page  514 

Longus   colli. — Description. — This   muscle  consists  of  three  portions, 


ANATOMY    IX    A    NUTSHELL.  585 

(a)  a  longitudinal  portion,  (b)  a  superior  oblique  portion,  (c)  inferior  oblique 
portion. 

Origin  of  the  longitudinal  portion  is  from  the  bodies  of  the  first,  second, 
and  third  dorsal,  and  of  the  sixth  and  seventh  cervical  vertebra?. 

Insertion  of  this  portion  into  the  body  of  the  second,  third,  and  fourth 
cervical  vertebra?. 

Origin  of  superior  oblique  portion  is  from  the  anterior  tubercle  of  the  trans- 
verse processes  of  the  third,  fourth,  and  fifth  cervical  vertebra?. 

Insertion  of  this  portion  into  the  anterior  tubercle  of  atlas. 

Origin  of  inferior  oblique  portion  is  from  the  bodies  of  the  first,  second,  and 
third  thoracic   vertebra?. 

Insertion  of  this  portion  is  into  the  anterior  tubercle  of  the  transverse 
processes  of  the  fifth  and  sixth  cervical  vertebra?. 

Action. — To  flex  the  cervical  portion  of  the  spinal  column,  and  rotates  it. 

Nerve  Supply. — Anterior  branches  of  the  lower  cervical  before  the}'  go 
into  the  brachial  plexus 

Blood  Supply. — 

Muscles  of  the  Lateral  Vertebral  Region. 

Scalenus  anttcus. — 

Origin. — From  the  anterior  tubercles  of  the  transverse  processes  of  the 
third,  fourth,  fifth,  and  sixth  cervical  vertebrae. 

Insertion. — Into  the  tubercle  on  the  inner  and  upper  surface  of  the  first 
rib  in  front  of  the  subclavian  artery. 

Action. — It  flexes  the  neck  and  elevates  the  first  rib. 

Xerve  Supply. — Anterior  primary  branches  of  the  fourth,  fifth,  and 
sixth  cervical  nerves. 

Blood  Supply. — 

Scalenus  medius. — Description. — Is  the  largest  of  the  Scaleni  muscles 
and  passing  through  its  substance  is  the  posterior  thoracic  or  long  thoracic 
nerve. 

Origin. — From  the  posterior  tubercles  of  the  transverse  processes  of  the 
lower  six  cervical  vertebrae. 

Insertion. — Into  the  upper  surface  of  the  first  rib  behind  the  groove  for 
the  subclavian  artery. 

Action. — It  flexes  the  cervical  portion  of  the  spinal  column  and  elevates 
the  first  rib. 

Xerve  Supply. — From  the  posterior  primary  branches  of  the  cervical 
nerves. 

Blood  Supply. — 

Scalenus  posticus. — Description. — Tlii<  is  the  smallest  and  deepest 
of  the  Scaleni  muscles  and  sometimes  blends  with  the  Scalenus  medius. 

Origin. — From  the  posterior  tubercle  of  the  transverse  processes  of  the 
lower  two  or  three  cervical  vertebra'. 

Insertion. — Into  the  outer  surface  of  the  second  rib  behind  the  origin 
of  the  Serratus  magnus. 

Action. — It  flexes  the  cervical  vertebrae  laterally  and  raises  the  Brs1  rib. 


586  ANATOMY    IN    A    NUTSHELL. 

Nerve  Supply. — From  the  lower  three  cervical  nerves. 
Blood  Supply. — 

Muscles  of  the  Larynx. 
Crico-thyroid. — Externa]  laryngeal  from  the  superior  laryngeal  Page  251 
Crico-arytenoideus  posticus. — Recurrent  laryngeal  branch  from  pneu- 

ni( igast  ric  nerve Page  251 

Crico-arytenoideus  lateralis. — Recurrent  laryngeal  branch  from  pneu- 

mogastric  uerve Page  251 

Arytenoideus.— -Recurrent    laryngeal    branch  from  pneumogastric    and 

superior  laryngeal  nerve Page  252 

Thyro-artenoideus. — Recurrent   laryngeal    branch   from   pneumogastric 

nerve Page  252 

Thyro-epiglottideus. — Recurrent  laryngeal  branch  from  pneumogastric 

nerve Page    252 

Aryteno-epiglottideus  superior. — Recurrent  laryngeal  nerve  Page  252 
ArytEno-epiglottideus  inferior. — Recurrent  laryngeal  nerve  Page  252 
Muscles  of  the  Back. 
First  layer. 
Trapezius.— Spinal  accessory,  third  and  fourth  cervical  nerves.  .Page    45 

LATISSIMUS  DORSI. — Middle  or  long  subscapular Page    52 

Second  layer. 
Levatob  ANGULI  suapul.e. — Third  and  fourth,  sometimes  the  fifth  Page    r>o 

Rhomboideus  .major. — Fifth  cervical   nerve Page    55 

Rhomboideus  minor. — Fifth  cervical  nerve Page    55 

Third  layer. 
Serratus  posticus  superior. — All  the  muscles  of  the  third  layer  Page  271 
Serratus  posticus  inferior — of  the  back  receive  the  external  Page  272 

Splenius  capitis. — divisions  of  the  posterior  branches Page  272 

Splenius  colli. — of  spinal  nerves  in  their  respective    regions.  .  .  .Page  272 
Fourth  layer. 

SACB  \l.     \M>    LUMBAR    REGIONS. 

Exectok  SPiNiE.-    External  division  of  posterior  branches  of  spinal  nerves 

Page  272 

I  tarsal  region. 
Ilio-Costalis.      Kxternal   division  of  posterior  branches  of  spinal  nerves 

Page    273 

Musci  i.i  s  \<  i  ejssorius  ad  ilio-costalem.—  External  division  of  posterior 

branches  of  spinal  nerves Page  274 

Longissimus    dorsi.    -External   division   of  posterior  branches  of  spinal 

nerves Page  274 

Spinalis  dorsi.     [nternal    division  of  posterior  branches  of  spinal  nerves 

Page  274 

<  tervical  region. 

Cervn  ojs  \><  endens.     External  division  of  posterior  branches  of  spinal 

nerve- Page  274 


ANATOMY    IN    A    NUTSHELL.  587 

Transveksalis  colli. — External  division  of  posterior  branches  of  spinal 

nerves Pag 

Trachelo-mastoid. — Internal  divisions  of  posterior  branches,  also  sub- 
occipital  and  great   oeeipitial   nerves Pag     27  ; 

Complexus. — Internal  divisions  of  posterior  branches,  also  suboccipital 

and  great  occipital  nerves 1 ':,  g<   271 

BrvENTEK    cervicis. — External  division  of    posterior  branches  of  spinal 

nerves Pag<   27f 

Spinalis  colli. — Internal  division  of  posterior  branches  of  spinal  nei 

Page  275 

Fifth   layer. 
Semispinalis    dorsi. — Internal    divisions    of    the    posterior    branches    of 

spinal  nerves Pagi   276 

Semispinalis  colli. — Internal  division-  of  the  posterior  branches  of  spinal 

nerves Page  J 7 < , 

Multifidtjs   spin.e. — Internal   divisions   of   posterior   branches   of   spinal 

nerves Page  276 

Rotatores  -pix.e. — Internal  divisions  of  the  posterior  branches  of  spinal 

nerves Page  276 

Supraspinales. — Internal  divisions  of  posterior  branches  of  spinal  ne 

Page  276 

Interspinales. — Internal  divisions  of  posterior  branches  of  spinal  nerves 

Page  278 

Extensor  coccyges. — Internal  division-  of  posterior  branches  of  spinal 

nerves Page  278 

Intertransversales. — Internal  division.-  of  posterior  branches  of  spinal 

nerves Page  278 

Rectus  capitis  posticus  major. — Suboccipital  nerve Page  -7s 

Rectus  capitis  posticus  minor. — Suboccipital  nerve Page  -7s 

Obliquus  capitis  superior. — Suboccipital  nerve Page  -7s 

Obliqtjus    capitis    inferior. — Suboccipital    and    greal    occipital    nerves 
' Page  280 

Thoracic  Region. 

Inter*  ostales   externi. — fntercostal  nerves Page  l>, 

Intercostales   interni. — Entercostal   nerves Page  158 

Infra*  ostales.  —  Intercostal    nerves Page  458 

Triangularis   sterni.-    Intercostal   nerves Page  l>s 

Levatores  costarum. — Intercostal   nerves Page  159 

Diaphragmatic  Region. 

Diaphragm.— Phrenic  plexus,  intercostal,  and  phrenic  nerves .. Page 233 

Superficial  Abdominal  Region. 

Obliquus  externus. — Lower  intercostal   nerves Page  160 

Obliquus    internus. — Lower    intercostals,    ilio-hypogastric,    - etiraes 

iUo-inguinal  nerve ''•''-'    "'' 


588  ANATOMY  IN  A  NUTSHELL. 

Transversalis. — Lower    intercostuls,    ilio-hypogastric,    sometimes    ilio- 
inguinal nerve Page  462 

Re(  ii  S    abdominis. — Lower  intercostal  nerves Page  463 

Pyramidalis. — Twelfth  thoracic  and  ili<  (-hypogastric  nerves.    ..Page  463 

Cremaster.— Genital  branch  of  genito-crural  nerve Page  464 

Deep  Abdominal  Region. 

Psoas  parvus. — Anterior  branch  of  first  lumbar  nerve Page  134 

Psoas  magnus.-  Anterior  branches  of  second  and  third  lumbar  Page  134 
Iliactjs. — Anterior   branches   of    second    and    third    lumbar   through   the 

anterior   crural    nerve Page  135 

Qu  \in;  \ti rs    lumborum. — Lower    intercostal    nerves Page  464 

Ischio-Rectal  Region  and  Perineum. 

Corrug  viok  cutis  ani. — Sympathetic  nerves Page  490 

External   sphincter   ani. — Anterior  division  of  fourth  sacral  and   in- 
ferior haemorrhoidal  branch  of  internal  pudic  nerve Page  490 

I  xtkkxal    sphincter    ani. — Hemorrhoidal Page  490 

Levator    ani. — Branches    from    anterior    division    of   fourth    sacral    and 

branches  from  pudic  nerve Page  490 

Coccygeus. — Branches  from  fourth  and  fifth  sacral  nerves Page  491 

In    the  male. 
Transversus  perin^ei. — Perineal  branch  of  internal  pudic  nervePage  491 
Accelerator  rnix.E. — Superficial  perineal  from  internal  pudic. Page  492 

Kkkctoh  pexik.     Perinea]  branch  of  internal  pudic  nerve Page  492 

Compressor  urethr.e. — Perineal  branch  of  internal  pudic  nerve  Page  492 

In  the  female. 
Ti;  lnsversus  p Hi !ix. Ei. — Perineal  branch  of  internal  pudic  nerve  Page  492 
Sphincter  vagix.e. — Perineal  branch  of  internal  pudic  nerve.. Page  493 
Erector  clitoridis. — Perineal  branch  of  internal  pudic  nerve  Page  493 
Compressor  urethra. — Perineal  branch  of  internal  pudic  nerve  Page  493 

Anterior  Thoracic  Region. 
Pectoralis    major. — External    and    internal    anterior    thoracic    nerves 

Page    41 

Pectoralis  minor. — Internal  anterior  thoracic  nerve Page    50 

Subclavitjs. — Fifth  and  sixth  cervical  nerves Page    42 

Lateral  Thoracic  Region. 
Serratus    MAGNUS. — Posterior    thoracic    from    the    fifth    and    sixth    and 

.seventh  cervical  nerves Page    54 

Acromial  Region. 

Deltoid. — Circumflex  nerve Page    43 

Anterior  Scapular  Region. 

Subscapulars.     Upper  and  lower  subscapular  nerves Page    56 

Posterior  Scapular  Region. 
Supraspinatus.     Fifth  and  sixth  cervical  through  suprascapular.  Page    56 
Infraspinatus. — Fifth  and  sixth  cervical  through  suprascapular. Page    55 
Teres  minor.-  Fifth  cervical  through  circumflex Page    56 


ANATOMY    IN    A    NUTSHELL.  589 

Teres  major. — Fifth  and  sixth  cervical  through  the  lower  subscapular 

Page  56 

Anterior  Humeral  Region. 

Coraco-brachtalis. — Musculo-cutaneous  nerve Page  58 

Biceps. — Musculo-cutaneous  nerve Page  58 

Brachialis  axticus. — Musculo-cutaneous  and  musculo-spiral .  .  .  .Page  79 

Posterior  Humeral  Region. 

Triceps. — Seventh  and  eighth  cervical  through  musculo-spiral.  .  I'air<-  50 

Subaxcoxeus. — Musculo-spiral  nerve Page  79 

Anterior  Radio-Ulnar  Region. 

Proxator  radii  teres. — Median  nerve Page  79 

Flexor  carpi  radialis. — Median  nerve Page  81 

Palmaris  loxgus. — Median-nerve Page  81 

Flexor  carpi  ulnaris. — Ulnar  nerve Page  81 

Flexor  sublimis  digitorum. — Median  nerve Page  82 

Flexor  profundus  digitorum. — Ulnar  and  anterior  interosseous.  Page  82 

Flexor  loxgus  pollicis. — Anterior  interosseous Page  84 

Proxator  quadratus. — Anterior  interosseous Page  84 

Radial   Region. 

Supinator  loxgus. — Musculo-spiral  nerve Page  84 

Extensor  carpi  radialis  loxgior. — Musculo-spiral  nerve Page  85 

Extexsor  carpi  radialis  brevior. — Posterior  interosseous.  .  .  .Page  s"> 
Posterior  Radio-Ulnar  Region. 

Extexsor  communis  digitorum. — Posterior  interosseous Page  85 

Extexsor  miximi  digiti. — Posterior  interosseous Page  87 

Extexsor  carpi  ulnaris. — 

Origix.  (1)  From  the  outer  condyle  of  thehumerus  bythe  common  tendon, 

adjacent  intermuscular  septa,  and  deep  fascia.  (2)  from  the  middle  third  of  the 

posterior  surface  of  the  ulna,  (3)  from  the  posterior  border  of  the  ulna  with  the 
Flexor  carpi  ulnaris  and  Flexor  profundus  digitorum. 

Insertion. — Into  the  ulnar  side  of  the  base  of  the  fifth  metacarpal  hone. 
Action. — To    extend    the    carpus. 
Nerve  Supply. — Posterior  interosseous. 
Blood  Supply. — Ulnar  artery. 

Anconeus. — Musculo-spiral  nerve Page  s7 

Supixator  brevis. — Posterior  interosseous  nerve Pag<  ss 

Extensor  ossis  metacarpi  pollicis. — Posterior  interosseous  nerve  P  ss 

Extensor  brevis  pollicis. — Posterior  interosseous  aerve Page  ss 

Extensor  longus  pollicis. — Posterior   interosseous   nerve ....  Page  91 

Extensor  indicis. — Posterior  interosseous  nerve Page  91 

Radial  Region  of  the   Hand. 

Abductor  pollicis. — Median  nerve Page  !  1  1 

Flexor  ossis  metacarpi  pollicis.-   Median  nerve Page  1  12 

Flexor  brevis  pollicis. — Median  and  ulnar  nerves Page  1 12 

Adductor  obliquus  pollicis. — Ulnar  nerve Page  1  L2 


590  ANATOMY  IN  A  NUTSHELL. 

Adductor  transversus  pollicis. — Ulnar  nerve Page  112 

Ulnar  Region. 

Palmaris   brevis. — Ulnar  nerve Page  113 

Abductor  minimi  digiti. — Ulnar  nerve Page  113 

Flexor  brevis  minimi  digiti. — Ulnar  nerve Page  113 

Flexor  ossis  metacarpi  minimi  digiti. — Ulnar  nerve Page  113 

Palmer  Region. 
Lumbricales. — Two    outer  ones   get   the     median;     two    inner    get   the 

ulnar  nerve Page  113 

The  three  palmar  interossei. — Ulnar  nerve Page  114 

The  four  dorsal  interossei. — Ulnar  nerve Page  114 

Iliac  Region. 
Psoas  magnus. — Anterior  branches  of  second  and  third  lumbar.  .Page  134 

Psoas  parvus. — Anterior  branch  of  the  first  lumbar Page  134 

Iliacus. — Anterior   branches   of  second,   and  third   lumbar  through   the 

anterior  crural  nerve Page  135 

Anterior  Femoral  Region. 
Tensor  vaginae  femoris. — Fourth  and  fifth  lumbar  and  first  sacral  through 

(lie  superior  gluteal  nerve Page  135 

Sartorius. — Anterior  crural Page  135 

Rectus. — Anterior  crural Page  136 

Vastus  externus. — Anterior  crural Page  137 

Vastus  internus. — Anterior  crural Page  137 

Crureus. — Anterior  crural Page  138 

Subcrureus. — Anterior  crural Page  138 

Internal  Femoral  Region. 
( rRACiLis. — Third  and  fourth  lumbar  through  the  obturator  nerve.  Page  138 
PectinetjS. — Anterior  crural,  obturator  accessory  and  occasionally  branch 

from  the  obturator  nerve Page  138 

Adductor  longus. — Obturator  nerve Page  140 

Adductor  brevis. — Obturator  nerve Page  140 

Adductor  magnus. — Obturator  and  great  sciatic  nerves Page  140 

Gluteal  Region. 
Gluteus  maximus. — Inferior  gluteal  and  small  sciatic  nerve.  .  .  .Page  141 

Gluteus  medius. — Superior  gluteal Page  141 

Gluteus  minimis. — Superior  gluteal Page  143 

Ia  riformis.-  First  and  second  sacral  nerves Page  143 

Gemellus  superior. — Fifth  lumbar,  first  and  second  sacral  nerves  Page  144 
Obturatob    [nternus. — Fifth    lumbar,    first    and    second    sacral    nerves 

Page  143 

Gemellus  inferior.— Fourth  and  fifth  lumbar,  and  first  sacral.  .Page  144 

Obturator  externus.     ( >bturator  nerve Page  144 

Quadratis  fi.mokis.      Last  lumbar  and  first  sacral  nerves Page  144 

Posterior  Femoral  Region. 

Biceps. — Great  sciatic  nerve Page  14C> 

SEMITENDINOSUS.-  ( iieat  sciatic  nerve Page  146 


ANATOMY    IN    A    NUTSHELL.  591 

Semimembranosus. — Great  sciatic  nerve Page  147 

Anterior  Tibio-Fibular  Region. 

Tibialis  anticus. — Anterior  tibial  nerve Page  152 

Extensor  longus  digitorum. — Anterior  tibial  nerve Pago  152 

Extensor  propius  halluces. — Anterior  tibial  nerve Pane  152 

Peroneus  tertius. — Anterior  tibial  nerve Page  loo 

Posterior  Tibio-Fibular  Region. 
Gastrocnemius.— Internal  popliteal  from  great  sciatic  nerve.  .  .  .  Page  153 

Plantaris. — Internal  popliteal  from  great  sciatic  nerve Page  154 

Soleus. — Internal  popliteal  and  posterior  tibial. Page  1  53 

Popliteus. — Internal  popliteal  nerve Page  154 

Flexor  longus  hallucis. — Fifth  lumbar,  first  and  second  sacral  through 

posterior   tibial   nerve : Page  1 54 

Flexor  longus  digitorum. — Posterior  tibial  nerve Page  156 

Tibialis  posticus. — Posterior  tibial  nerve Page  1  "fi 

Fibular  Region. 
Peroneus  longus. — Alusculo-cutaneous,  a  branch  of  external  popliteal 

nerves Page  15ii 

Peroneus   brevis. — Alusculo-cutaneous,   a   branch  of  external   popliteal 

narves Page  157 

Dorsal  Region  of  the  Foot. 

Extensor  brevis  digitorum. — Anterior  tibial  nerve Page  157 

Plantar  Region  of  the  Foot. 

Abductor  hallucis. — Internal  plantar  nerve Page  158 

Flexor  brevis  digitorum. — Internal  plantar  nerve Page  158 

Abductor  minimi  digiti. — External  plantar  nerve Page  158 

Flexor  accessories. — External  plantar  nerve Page  161 

Lumbricales. — The  two  inner  ones  get  the  internal  plantar  nerve,   the 

two  outer  ones  get  the  external  plantar  nerve Page  162 

Flexor  brevis  hallucis. — Internal  plantar  nerve Page  162 

Adductor  obliquus  hallucis. — External  plantar  nerve Page  158 

Flexor  brevis  minimi  digiti. — 

Origin. — From  the  base  of  the  fifth  metatarsal  bone  and  from  the  sheath 

of  the  tendon  of  the  Peroneus  longus. 

Insertion. — Into  the  base  of  the  first  phalanx  of  little  toe  and  fifth  meta- 
tarsal. 

Action. — To  flex  the  little  toe. 

Nerve  Supply. — External  plant;    . 

Blood  Supply. — External   plantar. 

Adductoe    transversus    hallucis    (pedis).     External    plantar    nerve 

Page  mo 

The  four  dorsal  lnterossei.     External  plantar  nerve.     The  firsl   and 

second  also  receive  extra  filaments  from  the  anterior  tibial  nerve Page  160 

The  three  plantar  enterossei.     External  plantar  nerve Page  L60 


INDEX. 


593 


INDEX 


Abdoinen,    307 

contents  of,  307-309 

regions  of,  307 

superficial  muscles  of,  460 

deep  muscles  of    464 

veins   of,    186 

lymphatics  of,  499 
Abdominal  ring  external,  476 

ring  internal,   477 

brain  function  of.  431 

aorta.   4.51-172 

aorta  relations  of,  451 

aorta  branches  of.  452 

anterior  trunk,  172 
Abducens  nerve,  439-392 
Abductor  hallucis  muscle,    158 

pollicifi  muscle,   111 

minimi  digiti  muscle,    113 
Accelerator  urinse  muscle,  492 

fibers  to  heart,  431 
Accessoriu^  muscle,  274 
Acetabulum,    131 
Acromial  thoracic  artery,  63 
Acromio-clavicular  articulation,  38 

clavicular   articulation   ligaments,    38 

clai  icular  articulation  blood  and  nerve  supply,  38 
Adductor  transversus  hallucis  muscle,  160 

obliquus   hallucis   muscle,    158 

magnus  muscle,   140 

brevis  muscle,  140 

longus  muscle.   140 

transversa  pollicis  muscle,  112 
Adductor  obliquus  pollicis  muscle,  112 
Adenology  definition  of,  17 
Adult   circulation,  39 
Ala  cinerea  of  brain,  443 
Alar  thoracic  artery,  64 
Alcock's  canal,  495-214 
Alimentary   canal,   309 
Allantois,  172 
Amaurosis,  373 
Amblyopia,  373 

Amphiarthrosis,  divisions  of,  26 
Anatomy  definition  of,  17 

divisions  of,   17 
Anastomotica  magna  artery  leu.    178 

magna  artery  (arm),  69 
Anconeus  muscle,  87 
Angular  vein,    180 
Angle  of  jaw.  543 
Angular  processes,  507 

gyrus,  345 

artery,  292 

Angiology   definition    of,    17 
Ankle  joint.   21)1-202 


Ankle  joint  blood  and  nerve  supply,  204 
joint  ligaments  of   203 

Annec'ent  gyrus,  345 

Annulu*  ovalis,   240 

Anosmia,  365 

Anterior  annular  ligament,  221-110 
Condyloid  foramen.  554 
cerebral  artery,   114 
communicating  artery,  444 
commissure  of  brain,  437-347 
cardiac  \  cm.  486 

commissure,  '■'•  17 

crual  nerve.  _'ln 

carpal  artery,  96-92 

circumflex  artery,  65 

el  hmoidal  arterj  .  385 

intercostal  arteries,   148 

ethmoidal  foramen.  553 

interosseous  artery,  95 

jugular  vein,  IM 
Antero-lateral  ground  bundle  tract,  433 

lateral  ascending  tract.  433 
Anterior  ligament.  61 

meningeal  artery,  444 

mediastinum    460 

nerve  roots.  333 

Spinal  arteries.  337 

tibial  nerve.  218 

tibial   vein     192 

tibial  artery,  1N4-1S0 

tibial  recurrent   arterj  .   182 

tibial  artery  branches  of,  182 

thoracic  artery.  64 

ulna    recurrent    artery,    95 
Antrum  of   Highmore,  537 
Ant ihelix  of  ear,  569 
Antitragicus  muscle,  570 

Aorta,    284 

Aortic  opening  of  diaphragm,  234 

plexus,   126 
Aponeurosis  description  of,  17 
Aqueduct  of  Syh  ius,  3  1 1 
Aqueduct  u~  \  est  ibuli, 
Aqueous  humor,  376 

Arachnoid  of  brain.  341 

Arachnoid  of  cord,  332 
\nii-  tendinous,   195 
Arch   aorta,   285 
Arm  cutaneous  nen es  of,   1 19 
veins  of,    117 
questions  on,    120 
lymphatics  of,    198 
muscles  • 
.  cent  ralis  ret  ina 
!  princeps  cen  ici 
receptaculi   artery,    ill 
A  Rvstem  description  of, 


594 

Arteries,  abdominal  aorta,  452-172 
acromial  thoracic,  63 
alar  thoracic,  li  1 
anastomotica  magna,  (leg),  178 
anastomotica  magna  (arm),  69 
anterior  circumflex,  65. 

carpal,  92-96 

cerebral,  444 

communicating,  444 

ethmoidal,  385 

interosseous,  95 

intercostal,   448 

meningeal,  444 

spinal,  337 

thoracic,  64 

tibial,    182-180 

ulna;    recurrent,  95 
aorta,  284 

articular  of  knee,  182 
ascending  cervical  449 

pharyngeal,  294 

palatine,  291 
angular,  292 
auricular,  293-294 
axillary,  62 
basilar,  448 
bladder   of,   472 
brachial,  66 
bronchial,  450 
calcanean.  186 
carotids.    286 
cerebellar,  448 
circle  of  Willis.  445 
ciliary,  385 
coats  of,  30 
coeliac  axis,  453 
common  interosseous,  95 
colica  dextra,  455 

media,   455 

sinistra,   455 
coronary,  244-292 
cremasteric,  560-176 
crico-thyroid,  290 
cutaneous  of  leg,  182 
cystic,  453 
deep  palmar  arch,  93 

ulnar,  90 

circumflex  iliac,  176-178 

epigastric,   175-178 
descending  palatine,  298 
digital,   186 
dorsalis  pollicis,  92 

indicia,  93 

pedis,  IM 

hallucis,    IM 

lingua',  291 
external    carotid,    1  i:i-288 
Artery  external  iliac,   175 
mammary,  6 1 
malleolar,  18  I 

plantar,    186 
tarsal,    1st 
facial,  291 

femoral,     170 


INDEX. 


Arjery,  frontal,  385 

gastro-epiploica   dextra,    453 

epiploica  sinistra,  453 
gastro-duodenalis,   453 
gastric,  453-327 
gluteal,   172 
hand    of,    106 
hepatic,  453 
hyoid,    288 
hypogastric,   33 
ileo-colic,  455 
ilio-lumbar,  172 
inferior  profunda,  66 

mesentery,  455 

thyroid,  449 

laryngeal,  449 

vesical,  172 

dental,  297 

labial,    292 
innominate,  286 
intercostal,  450 
internal   auditory,   448 

carotid,   443 

iliac,    172 

maxillary,  295 

malleolar,    182 

mammary,  448 

palpebral,    385 

pudic,  173 

tarsal.    184 
lachrymal,   383 
lingual,    290 
long  thoracic,  64 
lumbar,  452 
lateral     sacral,   172 
mediastinal,  448 
meningeal,  293 
mesenteric,  326 
metatarsal,  184 
metacarpal,  92 
middle  cerebral,  444 

meningeal,  296 

hemorrhoidal,   172 

vesical,   173 
musculo-phrenic,  449 
nasal,   385 
nutrient   rule  of,   19 
obturator,    172 
occipital,  293 
oesophageal,  450- 
ophthalmic,   383-444-308 
ovarian,    457 
palmar  recurrent,  95 

interossei,  94 
pancreatica?  parvse  and  magna,  453 
pericardiac,    450-448 
peroneal,   186 
phrenic,  44N-452 
plantar  digital,  184 
pterygoid,  297 
posterior  carpal,  92-96 

cerebral,  445 

circumflex,  65 

communicating,   445 


INDEX. 


595 


Artery,   ethmoidal,    384 
interosseous,  95 
mediastinal,  450 
perforating,  186 

scapular,   449 

spinal.    337 

tibial.  180-185 

tibial  recurrent.   182 

ulnar  recurrent,  95 
popliteal.    176 
princeps   pollicis.   93 
profunda,   176 
pterygo-palatine,  298 
pudic.    176 
pulmonary.   284 
pyloric.  4.53 
radial.  91 

radial   recurrent .   92 
radialis  indicia,  94 
ranine.  291 
renal.  456 
rule  of,  32 
sciatic.    174 
sigmoid,  455 
spheno-rnaxillary.    297 

palatine.  298 
splenic.   453-327 
spermatic.  456-567 
sternal,  448 
subclavian,   445 
sublingual,    291 
submaxillary.   291 
subscapular,   65 
submental.    292 
superficial   cervical,   449 
suprascapular.  449 
suprarenal.    456 
supraorbital,  384 
superficial  external  pudic.  17S 

circumflex  iliac.   178 

epigastric.  178 

femoral,    176 

palmar  arch,  96 
superficialis  volas,  92 
superfieial   descending.   288 
superior  intercostal.  449 

epigastric,  449 

mesentery.    454 

hemorrhoidal.   456 

vesical,  172 

fibular.    182 

profunda.    66 

perforating.    94 

thoracic.   62 

laryngeal.  288 

thyroid,  288 
sural.    182 

temporal,  294 
thoracic-  aorta,  451 
thyroid  a\i~.  449 
transver>alis,  colli,  449 
tonsillar,   291 

tracheal.    449 

tympanic,  295 


Artery,    ulnar,    95 

umbilical.   472 

uterine.  174 

vasa  aberrantia.  69 
brevia.   453 
intestini  tenuis,  451 

vas  deferens  of,   566 

vertebral.  447 

wrist  of,  92 

articular  of  knee.  182 
Articular  process  of  vertebra 
Articulation,  acromio-clavicular.   38 

ethmoid  bone  of,  525 

elbow  joint,  til 

femur.    150 

frontal  bone  of,  508 

hip-joint.    194 

humerus;   of,   61 

ilium   of.    128 

inferior  radioulnar,  79 
maxillary   bone   of,   543 
turbinated  bone  of,  546 

knee,  198 

lachrymal  bone  of.  532 

metatarsal  bone  of,  164 

metatarsophalangeal.  164 

metacarpophalangeal.    110 

middle  radioulnar,  78 

nasal  bone  of.  532 

occipital  bone  of,  513 

palate  bone  of,  549 

parietal  bone  of.   510 

pudic  bones  of,  128 

sacrum.  133 

sacro-vertebral    280 
iliac,   133 
coccygeal.    134 

sphenoidal  hone  of,  528 

sternoclavicular.    38 

superior  radio-ulnar.  78 

temporal  bone  of,  520 
Aryteno-epiglottideus  muscle.  252 
Arytenoideus  muscle.  252 
Ascending  cervical  artery.  449 

gyrus,    245 

palatine  artery.  291 

pharyngeal  artery,  294 

fibers  of  cord.   433 
Astigmatisn 
A~t  ragalus  bone,  162 

muscles  attached,    162 

Atla-   hone.   260 

muscles  attached,  260 
ligaments  of,  262 
Atlantoaxial  ligament 
Auerbach's  plexus 
Auditory  ner> «-.    8),  441 
meatus,  517 

nerve  superficial  origin,  579 
deep  origin 
cochlear  branch.  579 
vestibular  branch.  579 

canal  external.  570 

Auriculotemporal    nerve,    102 


596 


INDEX. 


Auricles  of  heart,  240-242 
Auricular   appendix,   240 
Auricular    artery,   293-295 
Axilla,    the    119 

boundaries  of,  1 19 

\  \illary  artery.  (12-98 
vein,    118-482 

\\i-  bone,  26  l 
Axis  bone  muscles  attached,  264 

ligaments  of,  265 
Azygos  veins,  483-484 

uvukr  muscle,  549 


Hack    -km    o/,    280 

muscles   of,  '270 
Basilar  artery,    1 18 

vein,  488 

process,  ."Hi" 
Bartholin's  glands,  563 

duct,  315 
Bicepa   muscle,   146-58 
Bicuspid   valve,  242 
Big  four.  319 

Hi  venter  cervicis  muscle,  274 
Bladder,    471 

urachus  of,  471 

arteries   of,   472 

ligaments   of,    472 

lymphatics,  500 
Blood  penis  vessels  of,  566 

vessels  description  of,  28 
Bone  as1  ragalus,  162 

atlas,  260 

axis,  264 

cavities  of,  22 

els  ■  Lcle,  35 

:cj  \.   I".  1 

cranium   of,  525-20 

cuboid,   162 

definition  of,  23 
eai    of,  574 
eminences  of,  _'_' 
Bones,  externa]   cuneiform,    164 
ethmoid,   •">-'  1 

tare.     2 

flat,  20 
femur,    1  17 
Bbula.  I7(i 
forearm  of,  69 
frontal,  506 
gladiolus,  236 
hand  of,  106 
humerus,  ti() 
In  oid,    5 19 
ilium.   I  25 
incus,    ">7  1 

internal   eimifonn     163 

inferior  maxillary.  .">  1 1 

turbinated,   546 
innominate,   128 
irregular,    2(1 
ischium,  127-129 


Bones,   labyrinth  of  ear,  576 

lachrymal,    532 

long,    19 

malar,    333 

malleus,    574 

manubrium,  236 

metacarpal,   106 

metatarsus,   164 

middle  cuneiform,  164 

middle   cuneiform,    164 

nasal,    531 

non-articular  cavities  of,  22 

navicular.  163 

occipital,   511 

orbit  of,  368 

os  calcis,   162 

palate,   547 

parietal,    509 

pelvis,    131 

phalanges,  164 

processes  definition  of,  19 

prominences  of,  22 

pubic.    127 

pubis,    128 

radius,  69 

rib,  268 

sacrum,  132 

scapuhe,  45 

sesamoid,  20-168 

short,   20 

sphenoid,  526 

stapes,   574 

sternum,   236 

superior  maxillary,  535 

temporal,  516 

tibia.  166 

turbinated,    528 

ulna,    69 

vertebra,   258 

vomer,  546 

Wormian,  2 
Brain,    339 

ala  cinerea,  443 

anterior  commissures  of,  437-347 

choroid  plexuses  of,  441 

conductor  sonorous  of,  443 

cortex  of.  340 

corpus  callosum  of,  350-437 
striatum  of,  441 

coverings  of,  341 

crura  cerebri  of,  363-437 

divisions  of,  341 

definition  of,   i:>7 

eminentia  teres,   443 

fasciculus   unciformis,   443 

fissures  of.   342-343 

fornix.    348-437 

fourth  ventricle,  439 

fovea  superior,  443 
inferior.    443 

ganglia  of.  343 

gyri  of,  345 

inferior  medullary  velum,  441 

infundibulum,   441 


INDEX. 


597 


Brain    lateral  ventricle,  438 

lamina  cinerea,  441 

ligula.  443 

lobes  of.  344-342 

longitudinal  commissures.  340-437 

locus  cseruleus.  443 

middle  commissure.  348-437 

obex,  443 
Brain,  olfactory  tract.  365-437 

optic   commissure.   437-366 

peduncles  of.  354 
pineal   gland     441 

pons  varolii,  362-437 

posterior  commissure.  437-348 
perforated  space.  441 

ta?nia  semicircularii,  356-437 

tela  choroidia  inferior.  441 

third  ventricle.  437 

transverse  commissures.  339-437 

trigonum  hypoglossi.  443 

tuber  cinereum.  441 

tuberculum    acusticum.    443 

ventricles.  340-358 

valve  of  Yieussens   441 
Brachial  plexus.  96 

communicating  branches,  98 

artery.  66 

relations  of,  66 
Brachialis  amicus  muscle.  79 
Bronchus,    254 
Bronchial   veins.    4^4 

arteries.  450 

Brunner's   glands,   321 
Bryant's   triangle.    196 
Buccal   nerve.   40_> 
Buccinator  muscle.  540 
Buck's   fascia.  495 
Bulbus  vestibuli.   563 


Cseeum.  320 
Calcarine  fissure.  344 
Calcaneo-cuboid  ligamei.-  -    - 
Calloso-marginal  fissure.  343 
Call"--al  gyrus,  34.5 
Canal  of  Nuck.  559 
Cardiac    nerves.   416 
plexus,  424 
veins.    244 
Cardio-inhibitory   center,   359 
Carotid  arteries.  286 

relations  of,  2>-7 
artery  external,   443 

internal,    443 
Carotid  sheath,  282 

triangle,  superior,  280 

inferior.  282 
Carotid  plexu-.  422 
Capillarir-s.  description  of,  30 
Capsular  ligament.  48 

of  knee.   : 


Capsule  of  Muller,  47" 

of  Tenon 
Cauda   equina,   331 
Cavernou-  sinus  -.    189 

plexu-.   422 
Cell-   of   Sehultz 
Center  definition   for.   364 
Centers  in  medulla.  359 
Center  for  smell, 
Central  canal  of  cord,  333 
Central  lobe  of  brain,  344 

-ystem.  339 

tendon   perineum.   495 
Centrifugal    nerves,   431 
Centripetal   nerves,   431 
Cerebrum  location  of.  356 
Cerebellum  fi— tires  of.  354 
Cerebrum  lobe-  of.  344 

exterior  of.  342 
Cerebellar   vein-. 
Cerebral  veil 

hernia.   474 
Cerebellar  artery.  448 
Cerebellum  description  of,  357-360 

nuclei  of,  361 

peduncles  of,  360-362 
Cervicalis  ascendens  muscle.  27  5 
Cervical  nerves.  298 

plexus.   304 

branches  of  305 
communicating  branche-.  98 
Cervical    nerves     second,    301 
third.  303 

pleura.  256 

vertebrae.  264 
Cervix,  laceration  of.  431 
Chiasma,    366-357 
Chondro-glossus  muscle,  550 
Chopart's  amputation,  194 
Choroid  plexuses  of  brain,  441 
Choroid  coat  of  eye,  381-376 
Chord*  tendinea1,  241-243 
Ciliary    ganglion.    395-403 
Ciliary  body,  386 

arteries.     - 
Circle  of  Willis.  44.'. 
Circular  sinus 
Circumvallate  papillse,  311 
Circumflex  nerve,  99 
Circumpatellar  anaston 
Clavicle  articular  blood  supi 1] 

articulatioi 

liean  . 

muscles  attached,   I" 
Cliton- 

134 
muscles  attached,  1 3 1 
_-.-u-  muscle,    191 
2 1  *> 
• 


598 


INDEX. 


Cceliac  axis,    153 

plexus,   l-'"> 
Colles's  fascia,  494 
Colica-dextra    artery,    455 

media  artery,  455 
Colica  sinistra  artery,  455 
( lolon  ascending,  320 

descending,  320 
Colon,  transverse,    320 
Columns  of  Bertin,  468 

Of  Clarke,   333 

Columns  carneae,  24  1-2  13 
( !omes  nervi  phrenici,  307 
Common  carotid  arteries,  288 

intero us  artery,  95 

Commissures  of  brain,  339 
Communicans   hypoglossi    nerve,   306 
Compressor  urethra'  muscle,  492-493 

nasi  muscle,  539 
Complete  fissure,  342 
Complexus  muscle,  274 
t  lonarium,  353 
Concha   of  car,   570 
Conducting  paths  of  brain,  431 
Conductor  sonorous,  443 
Condyles,  22-61 
( londyloid  foramen,  51 1 
Congenital  hernia,  478 

Imi  nia   kind-  of,  478 

Conus  arteriosus,  241 
medullaris,   331 
Coraco  brachialis  muscle,  58 
Conjunctiva,  388 
Cord  membranes  of,  332 

tracts     ,,f,     433 
I  !oi  tex  centers  of,  433 

Coi  pus  Arantii,  242 
callosus,  350-437 

call. .Mini,  319-350 

dent  at  um,  361 

Cor]  hi-  striatum,  441 

Corpora  cavernosa  penis,  565 
Corpus  lutetim  of  ovary,  561 
Coi  pora     triata,  347 
( !oi  nea  of  eye,  378 

-t  met  tire  of,   USD 
I  Hi.. nary   sinus.   486-240-244 

arteries,  211-292 

valve,    240 
Corrugator  cutis  ani  muscle,  490 

supercili)  muscle,  508  "** 
Cortical  substance  of  kidney,  469 
Cortes  of  brain  coi  meet  ion  of,  431 

Of    I. lam.    340 
<',,-.,,  clavicular    ligament,    38 
Costal    pleura,  256 
Cotyloid    ligament,    196 
Cowper'e  (.'land,  137  195 

Cranial   ner\  es      139 

nen  e  second,  366 
nerves  description  of,  364-27 
nerve-   rule   of   origin,   364 
nerves  table  of,  27 
Cremastei     muscle      Hit 


Cremasteric  artery,  566-176 

fascia,  567-568 
Cribriform  plate,  524 

fascia,  218 
Crico-aryt enoideus  lateralis  muscle,  251 
muscle,  251 

thyroid  artery,  290 

thyroid   muscle,  251 
Crista   galli,   525 

vestibuli  of  ear,  577 
Crista   urethra,  473 
Crural  hernia,  474 
Crucial    anastomosis,    174 

ligaments,  knee,  200 
atlas,  264 
Crura    cerebri,    363-437 
Crureus  muscle,   138 
Crus  cerebri,  363 
Crusta  petrosa,  31 1 
Crystalline  humor  of  eye,  376 
Cuboid  bone,  162 

articulation  of,  162 
muscles   attached,    162 
Cutaneous  arteries  of  leg,  182 

nerves.  214 

membrane  description  of,  465 
Cuneate  gyrus,  345 
Cystic  artery,  453 

vein,  485 

goitre,    246 


Dartos  of  penis,  565 

Deep  lymphatic  vessels,  498 

cervical  vein,  482 
Dental  canal  inferior,  543 
Depressor  alee  nasi  muscle,  539 
Deciduous  teeth,  309 
Deep  circumflex  iliac  artery,   176 

epigastric  artery,   175 

fascia  of  arm,  115 

ulnar  artery  branch,  96 

palmar  arch,  93 
Definition  of  center,   364 
Degeneration  of  cord,  334 
Deltoid  muscle.  43 
Dental  nerves,  398 
Dentate  gyrus,  346 

fissure,   342 
Dentine  of  teeth,  311 
Depressor  labii  inferioris  muscle,  544 

anguli  oris  muscle,  545 
Dermatology   definition   of,    17 
Descending  fibers  of  cord,  335 

palatine   artery,  298 
Diabetic  center,   359 
Diaphragm    muscle,    233 
crus  of,  234 
openings  in,  234 
Diaphragmatic  pleura,  256 

plexus, 
Diarthrosis  divisions  of,  26 
Diastole  of  heart.  245 


[NDEX. 


Digastric  muscle,  521 

triangle,  282 
Digital   arteries,   186 
Dilator  nares  posterior  muscle,  540 
Diplce  veins  of,  486 
Direct  cerebellar  tracts,  434 
inguinal  hernia,  474 

coverings  of       475 
Dorsi-spinal  veins,  486 
Discus  proligerus  of  ovum,  561 
Diseases  of  spinal  cord,  334 
Dorsalis  linguae  artery.  291 
Dorsal  interossei  muscle,  160-114 
Dorsalis  pedis  artery,  184 
hallucis    artery.    184 
Dorsales  indicis  artery,  93 

pollicis   artery,   92 
Duct  of  Gartner,  563 
Ductus  arteriosus,   the  33 
Duodenum,   320 
Dura  Mater  of  cord,  332 

blood  supply,  341 

nerve  supply,  341 

sinuses  of,  488 

veins  of,  480 


Ear,    568 

bones  of,   574 

internal,   576 

intrinsic  muscles  of,  570 

nerve  of,  577 

pinna,    569 

tympanum  of,  571 

vestibule,  5777 
Ejaculatory   duct,   567 
Elbow  joint,  61 

ligaments  of,  61 
Eleventh  nerve,  416 
Eminentia  teres,  443 
Emissary  veins,  487 
Emmet ropia,    375 
Enamel  of  teeth,  311 
Encephalon,   341 
Encysted  hernia,  479 
Endocardium,  244 
Ensiform    appendix,   237 
Epigastric   region,   309 
Epiblast,   331 
Epididymis,  568 
Epiphysis,  353 
Epeneephalon,   341 
Epiglottis,  250 
Erector  clitoridia  muscle,  493 
Erector  penis  muscle,  492 

spinse  muscle,  272 
Esophagus,  31 1 

coats  of,  317 
Ethmoid  bone,  524 

crista  galli  of,  525 
foramina  of,  525 
nasal   slit,  525 
processes  of,  525 


Ethmoid  bone,  muscles  attached,   •">-'•' 

cribriform  plate  of,  525 
Ethmoidal   > 
Ethmoid   notch,   ">o7 
Eustachian  tube,  .".7  <• 

valve.    2 1(1 
Exophthalmic  goitre,  -'  16 
Extensor  carpi-radialis  longior  muscle    35 
Extensor  brevis  pollicis  muscle,  88 
digitorum  muscle,   157 
carpi-radialis  brevior  muscle,  85 
communis  digitorum  muscle,  85 
coccygis  muscle,  278 
indicis  muscle,  91 
longus  pollicis  muscle,  91 
digitorium  muscle,   L52 
iiiiiiimi  digil i  muscle,  87 
<i~-i~  metacarpi  pollicis  muscle,  y^ 
proprius   hallucis    muscle,    152 
Externa]  abdominal  ring,  476 
annular  ligament.  222 
auditory  canal,  570 
blood  supply  of,  570 
nerve  supply  of,  .">7<t 
carotid  artery,    1  13 
cuneiform    bone,    I  til 

muscles    attached.     104 

cutaneous  nen  e,  210 

ear,  568-569 

blood  and  nerve  supply  of,  570 

genitals,  female,  562 

iliac  artery.    17"> 

iliac  vein,   186 

intermuscular   septum    (leg>,   219 
arm),  115 

intercostal  muscles,  457 

jugular  vein,  481 

lateral  ligament .  til' 

malleolar  artery,  184 

mammary  artery,  64 

orbital   gyrus,   345 

plantar  artery.   186 
nerve.    216 

pterygoid  muscle,  ■">-'!» 

rectu>  muscle,  531 

sphincter  ani  muscle,   190 

tarsal  arterj  ,184 

thoracic  nerve,  us 
Extrinsic  ligaments  "t  larynx,  250 
Eye-ball,  3<;s 

coal  a  of,  376 

refracting  media.  376 

blood  supply  of,  382 
Eye-brows,  389 
Eye  diseases  of,  373 
Eye  lashes,  389 

I  ye  lid-.  389 

I  \.    muscles  of,  ■">-''' 

•  nsorj    ligament    .-: 


Face  1\  mpii.it  ice  "i . 
nerves  ol 


600 


INDEX. 


Facial  artery,  391 

nerve,  407-439 

superficial  origin,    106 
vein,  480 
Falciform  process,  220 
Fallopian  tubes,  559 
ampulla,    560 
fimbria.    560 
isthmus,   560 
i  u]j  proprli,   133 

Fasciculus  unciformus,  437-443 
Fascia  arm  form--  of,  115 
Buck's,    195 
cribriform,    218 
thigh    deep    of,    219 

description    of,    17 
band  of,  116 
lata.    219-220 
of  leg,   220 
obturator,    495 

plantar.  223 

■  >f   perineum,     V.t.~> 

of  pelvic,  495 

recto-vesical,    195 

superficial  of  thigh,  2 1  s 
I  auces,  316 
I  iinale  organs  of  generation  external.  .">ti2 

organs  of  generation,  556 

pelvic,    132 

uretbra,    474 
Femoral  artery,   176 

brancbe-  of,   178 
relations  of     176 
■anal.   477 

hernia,   477 

sheath,    177 

ring,    178 

brevia  hallucis  muscle,  162 

brevia  digitorum  muscle,  158 

minimi   digiti   muscle,    1  13 

bre\i>  pollicis  muscle,  11- 

carpi  ulnaris  muscle,  81 

carpi  radialis  muscle,  81 

sublimit  digitorum  muscle,  82 

of  hip  joint ,    196 

longus   digitorum    muscle,    15*6 

longus  hallucis  muscle,  15  l 

longus  pollicis  muscle,  84 

profundus  digitorum   muscle    82 
Floating  kidney    169 
Foramina  of  Stenson,  538 

of  Scarp 

base  "f  skull,  552 

of  orbit.  369 

of  Thebesii,  240 
Foramen  <  tecum,  ~<r,j 

caecum  of  tongue,    :i 3 

lacerum  medium,  553 

magnum,   511-332 

Monro,  .:)! 

ovale,  527 

rotundum,  r,J7 

Bpinosum,  553-527 

Vesalii,  527  553 


Foramen    of  Winslow.  465 

of   Win-low  relations  of.  465 
Fire-arm   description  of,   69 

radial  region,  69 

posterior  radio-ulnar  region,  69 

bones  of,  69 
Formatio  reticularis,  363 
Fornix,  348-437 

description    of,    356 

pillars   of,    349 
Fossa  of  helix,  569 

navicularis  of  urethra.   17  1 

ovalis,   240 
Fourth  ventricle  boundaries  of,  439 

nerve.    391 

ventricle,  358 
Fovea  cochlearis,  577 

hemispherica,   577 

inferior  and  superior  of  brain.  4-t3 
Fractures  of  spinal  column,  334 
Frsenum  lingua?,  313 
Frontal  artery,  385 

bone,  506 

bone  nutrient  artery  of,  508 

bone  muscle  attached,  508 

bone  sinuses  of,  507 

lobe  of  brain,  344 

gyri,   345 

nerve,  394 
Frontal   sinuses.   507 

vein,  487-480 
Funiculus   cuneatus,   360 

gracilis,  360 

Rolando,  360 
Fungiform  papilla?,  311 


Gall  bladder,  325 
Ganglion   of  trunk,   412 

of    root.    412 
Gasserian  ganglion,  402 
Gastric  artery,  327-453 

glands,  318 

nerves,   416 

plexus,   425 

vein,  484 
Gastro-duodenalis   artery,   453 

epiploica  sinistra  artery,  453 

epiploica  dextra  artery,  453 
cnemius   muscle,   153 
Gemellus  superior  muscle,   144 

inferior   muscle,    144 
Genesiology  definition  of,  17 
Geniculate  bodies,   352 
Genio-hyo-glossus  muscle,  544 

hyoideus  muscle,  544 
Genito-crual  nerve,  278 
Gimbernat's    ligament,     177 
Glabella  of  frontal  bone,  506 
Gladioli-    236 
GlancL  of  Lit t  re.  474 
Glaserian   fissure,   573 
Glosso-pharyngea]  nerve  (9th),  441-41o 


[NDEX. 


601 


Gluteal  aponeurosis,  220 
Gluteus   maximus  muscle,    141 

medius  muscle,    141 

minimus   muscle,    143 
Goitre.   246 

Goll  and  Burdach  tracts,  433 
Gower's   tract,   433 
Graafian  follicles,  561 
Gracilis  muscle,  138 
Gray  rami  communieantes,   128-421 

nuclei   of   cerebellum,   362 
Great  auricular  nerve,  305 

cardiac  vein,   185 

omentum,  318 

sciatic  nerve,  215 

superficial  petrosal  nerve,  404 
Greater  sac  of  peritoneum,  466 
Greater  trochanter  of  femur,  149 
Gubernaculum  testis,  568 
Gyri,  342-345 

operti,    346 
Gyrus  fornicatus  of  brain,  4.37 

H 

Hand  description  of,  106 

bones   of,    106 

muscles   of.    111 

questions  on.   121) 
Hancock's    amputation,    194 
Hard   palate,    315 
Heart  description  of.  238-46 

auricles   of.   242 

blood   supply,   238-244 

nerve,    23S-245 

fibers  of,  243 

lymphatics   of,   503 

location  of.  239 

moderator  Kami  of,  242 

openings   in.  240 

systole  of.  2  15 

dyastole  of.   2  45 

sounds  of,  246 

valves  location  of.  246 
Heart  ventricles  of,  246 

veins  of,  485 

weight  of,  239 
Head   lymphatics   of.   504 

lymph  nodes  of.  505 
Helix  of  ear,  569 
Helicis  major  muscle,  570 

minor   muscles,   570 
Hernia  congenital,  478 

causes  of,   175 

cerebral.    47  ! 

crural.    474 

direct  inguinal,  17  I 

indirect,     (7  1 

lumbar,  474 

phrenic,    474 

description  of.  474 

encysted,    179 

funicular,  478 

femoral,    477 


Hernia,  infantile,    478 

strangulated,   475 

umbilical,  475 

tunica  vaginalis  testis,    17s 
Hemianopsia,   374 
Hemorrhage  of  pons,   363 
Hilton'-   law,   25 

Horizontal  fissure  of  cerebellum,  35 1 
Horner's  m  isrle    '■'■7 ■'. 
Hepatic  arterj  ■    15  I 

duct.    326 

flexure.   320 

plexus,    12.". 

veins,  190 

veins  division  of,  190 
Hippocampal  gyrus,  345 
Hip-joint,  description  of,  194 

articular  nerves,  212 

capsular  ligament,  19 1 

crucial  anastomosis,  174 

extensors,  l'.n; 

blood   supply,   196 

nerve    supply,    196 

ligaments  of,    194 

synovial   membrane  of.    km; 
Hey's  amputation,  194 
Hiluin  of  kidney.  469 
Humerus,  description  of.  60 

1  uberositj   of  greater  and  lesser,  tin 

border-    of.    till 

condyles  of.  til 
nutrient  of,  69 
surfaces  of.  til 

Hunter'-  canal.   L76 

Hydatid  of  Morgagni,  560-563 

Hymen.  556 

Hyoid    artery,    288 

bone,  549 

cornua   of,   55m 

b ■,  muscles  of.  5511 

Hyo-glossus  muscle,  550 
Hyperosmia,  365 
Hypermetropia,   374 
Hypochondriac,  right,  left.  307-309 
Hypogastric,  307-309 

arteries,   ■'•■■ 

plexus,    127 

1  'ircumpatellar  anasti  imosis,   1  82 
Hypoglossal  nerve,  417-141 

lie!   \  ,  ..  .Ill  111  111  I  KM  t  loll.     \\S 

nerve  branches  of  distribution,    lis 


tleo-cecal  valve, 

Iliac  ai terj   relations  of,  1 7  1 

fossa,  126 

notch,    126 

veins,  188 
Uiacua  muscles,  1 35 

II !l  4li'     .11  tel  J  .       I'.'i 

limn. 

bone  descripl  ion  of.  1 25 
artioulati f.  1  -'7 


602 


INDEX. 


Ilium,  muscles  attached,   L28 
Qio-costalis  muscle,  273 
Ilio-fenidial  ligament,  194 
Ilio-hypogastric  aerve,  208 

inguinal  nerve,  208 

tibial    band,   220 
Impar  ganglion,    123 
Incisura  cerebelli,  354 
Incus    bone,    574 
Inguinal  hernia  indirect,   174 

hernia  indirect   coverings  of,  475 
Indirect  route  for  fibers.  433 
Infantile    hernia.    478 
Inferior  cerebral  veins.  4N7 

cervical  ganglion,  422 

dental   artery.   207 
dental  canal.  543 
dental  nerve,   M)2 
gluteal  nerve,  214 
laryngeal  artery,  440 
lingualis    muscle,   557 
longitudinal  sinus,  489 
maxillary   bone,   541 

borders  of,  541 

surface-   of,   541 

rami  of,  542 

dental  canal  of,  543 

muscles   attached,   543 
maxillary  nerve,  399 
medullary  velum  of  brain,  441 
mesentery  artery.  455 
mesenteric  vein,  484 
mesenteric  plexus,  420 
thyroid  artery,   440 
turbinated   bone,  546 

articulations  of,   546 

ossification  of,  540 

muscles    attached,    546 

oblique  muscle,  538 
petrosal    sinuses,   490 

profunda  artery,  66 

radio-ulnar  articulation,  79 

rectus    muscle.    530 

vena  cava.   188 

vessical  artery,   172 
Infraspinatus    muscle.    55 
Infracostal   muscle,    158 
Infundibulum  of  brain,  441-437 
Infundibuliform  fascia,  568-567 
Infundibulum  of  heart,  241 

Inguinal   canal.    17."i 

canal    relation   of,    175 
Innominate  articulations.  1  2S 
Innominate   artery.    286 

bone.    128 

vein-.    482-483 

Intercostal  arteries,  451 

arteries,   branches   of,    151 

-pace  content-  of,  451 
Intercolumnar    fascia.    50N-507 
Intermuscular  septum  of  leg,  218 

Internal  abdominal   ring,  477 
annular  ligament .   222 

auditory   artery,    148 


Internal  ear  blood  supply,  578 

auditory   meatus,    577-553 

carotid   artery,   443 

cavernous  portion  of,  443 
cervical   portion   of,   443 
petrous  portion  of,  443 
relations   of,    445 

capsule,  352 

cremasteric  muscle,  567 

cuneiform  bone,   163 

cuneiform  muscle.-  attached.   104 

cutaneous   nerve,    106 

ear,    570 

ear  nerve  supply,  578 

iliac    artery,    172 

iliac    vein,    188 

intercostal  muscles,  458 

intermuscular    septum,    115-60 

jugular  vein,  481 

lateral  ligament,  62 

malleolar   artery,    182 
Internal  mammary  artery,  448 

maxillary  vein,  480 

maxillary,  295 

mammary  nodes,  502 

palpebral   artery,   385 

plantar   nerve,   216 

pterygoid  muscle,  529 

pudic  artery,  173 

rectus   muscle.    531 

sphincter  ani   muscle,   490 

tar-al  artery,  184 

thoracic    nerve,    99 

tibial  artery,   186 
Intestines,  320 

nerve    supply,    322 

blood  supply  of,  323-321 

glands    of,    321-322 

lymphatics   of,    501 
Interspinous    ligament,    268 
Interspinales  muscles,  278 
Intertrans\  ersales   muscle,  278 
Iris,    386 
Ischio  capsular  ligament.  194 

rectal  fossa,  494 

rectal  region  muscles  of.  490 
Ischium,  127 

muscles  attached,  128 

acetabulum,  131 
Island  of   Reil,   344 
Interchordse    posterius,    573 


Jacobson's  nerve,  410 
Jaw,   angle   of,   543 
.Jejunum.   32 
.loints,  division  of,  25 

elbuw,  61 

ligaments,  description  of,  24 

shoulder,  48 

knee.  179 

wrist,   78 
Jugular  foramen,   511,    553 

ganglion,    410 


INDEX. 


K 

Kakosmia,  365 

Ki<lney.  blood  supply  of,  4i i8-  ■' 

columns  of   Bertin.   4(is 

cortical   substance  of,  469 

description   of,   4ti7 

dimensions  of,  468 

function    of,    469 

hiluni    of,    469 

lymphatics  of,   501 

medullary    portion,   468 

Malpighian  pyramids  of,  469 

nerve  supply  of,  4tjs-47i> 

pyramids  of  Ferrin.  468 

pelvis    of,    469 

relations  of  its  vessel-.  4ds 

relation  of,  468 

<car  of.  468 

tubes  Bellini,  470 

tubes    Ferrein.    470 

tube-   Henle.   470 

uriniferous  tubules  of.  46S 
Knee-joint,  description  of,   19s 

blood   supply.    179-19S 

incorporated  tendons  of.  198 

joint,  nerve.  198 

flexors.    198 

extensors.  198 

ligaments  of    198 


Labial  nerve.  399 
Labial  artery.  292 
Labia    majora.   562 

minora.  562 
Lacerations  of  cervix.  431-559 
Lachrymal    artery.    383 

bone.  532 

bone   muscles   attached.   532 

f(  --a.  507 

gland       87 

nerve.    394 
Lacteals,   501 
Lacuna   magna     47:-! 
Lamina  cinerea  of  brain,  345-437-441 

cribrosa,    378 

spiralis  of  ear.  577 

of  vertebra-.   258 
Large  deep  petrosal  nerve.  4(14 

intestine-.   32(1-322 
Larynx.  249 

ligaments  of,  250 

muscle-  of,  250 

sinus  of,  250 
Lateral  sinus,    189 

ventricle.  358 

ventricle  boundary  of,  43s 
Latissimu-  dorai   muscle,  52 
Left  cardiac  vein,  485 
Left  innominate  vein.  483 
Leg.  vena  comites,    192 

lymphatics   of.   498 


Leg,  lymph    nodes   of,   499 

Lenticular   ganglion.    U 

Lesser  internal  cutaneous  nerve.  106 

k  of  peritoneum.    • 
Leva  mi  muscles,  459 

Levator  anguli  scapohe  must 
anguli   ori-   mus 
ani  muscle.  49(1 
labii  mferioris  muscle,  545 
labii  superioris  proprius  muscle,  540-534 
palpebral  mu-cl. 
palati  muscle, 

labii  superioris  ala?que  na-i  muse  ■ 
Lieberkuhn    gaud-.    32] 
Ligamentous  muscles  of  kne. 
Ligament  a   denticulata.   333 

vaginalis,   llti 
Ligamentum  teres,   196 
mucosum,  202 
patella.  198 
pectinatum   iridis.   380 
alaria.    202 
Ligaments,  atlanto-axia 
anterior.    6 

anterior   annular.    116-221 
Gimbernat'-.    477 
triangular.  477 
Pourpart'-.    477 
Winslowii,  198 
of  Zinn.  322 

astragali  and  scaphoid,  2n4 
of   ankle-joint.    203 
acromio-claviculai 
broad  vein  of.    190 
of  bladder.  472 
crucial  of  at  la-.  2(14 
capsular.    194 

coraco-humeral,  4s 
of  clavicle.  38 

-clavicular.    38 
description  of.  26 
external  lateral.  62 
glenoid.    48 
of  hip-joint .   194 
interosseous,    206 
ischio-capsular,    194 
ilio-femoral,   194 
internal  lateral.  62 
of  liver.  324 
odontoid,  264 
occipito-atlantal,  260-261 
•  •-  calcis  and  cuboid,  206 
"-  calcis  and  scaphoid,  204 
os  calcis  and  astragalus,   - 
posterior  annular.   1  16 
posterioi 

of   radio-ulnar   articulation,    79 
of  scapulav, 

scaphoid,  cuboid,  Uuneiform,  -'07 
transverse,   is 

of  wri-t-ji' 
I.igula  of  brai 
Lines  aspera  of  femui .  1  i1' 


604 


INDEX. 


Linea  splendens,    333 
Lingual  artery,  290 
nerve.  402-411 

Lisfranc's  amputation,  194 

Little  four,  319 

Liver,  description  of,  324 

blood  supply  of,  324 

nerve  supply  of,  32  1 

deep  vessels,  329 

lymphatics  <>f.  501 

ligament  -  of,   32  1 

lobes  of,  324 

relations  of,  324 

superficial  vessels    328 
gels  of,  190 
Lobes  of  cerebellum,  344-361 

»f  liver.   324 
Lobule  of  ear,   569 
Locus  coeruleus  of  brain,  443 

Locomotor    ataxia.    334 

J. iing  thoracic  artery,  6 1 

subscapular  nerve,  99 
Longitudinal  commissures  of  brain,  340-437 
Longissmus  dorsi   muscle.   _'7 1 

extremity   veins.    192 
Lumbar  arteries,    152 

hernia.   474 

nodes,   500 

plexus,  208 

plexus,  blood  supply  of,  212 

region  right   and  left.  307 

ganglia  of  sympathetic,  428 

veins.    188 
Lumbricales  muscles  of  hand,  113 

muscles  of  foot,   162 
Lungs.    !!.""> 4 

nerves  of,  416 

roots  of,  257 

blood  supply  of,  255 

nerve   supply   of,   256 

lymphatics   of,   502 
Lymph,  description  of,    117 
Lymphatic-  of  abdomen,  499 

Of    arm.     198 

of  bladder.  500 

description  of,    196 

duct.    196 

of  face.  .",ii  | 
of  head.  .",11  1 
Of  heart.   503 

of  intestines,   501-320-322 

Of  kidney.  .",111 

of  leg,  199 

of  liver,  501 

of  lower  extremities,  199 

of  lung,   502 

of  mouth.  505 

of   neck.   504 

tunic.      PI7 

superficial  and  deep,  498 
oesophagus 

..rbit.    ",ii  I 
pan 

pelvis,    199 


Lymphatics  of  pharynx,  505 
rectum,  500 

renal,  471 

of   scalp,   503 

of   spleen.   501 

of    stomach.    501 

supra-hyoid,  504 
Lymphatic  system,  490 

of  testicle,  501 

of    thoracic    wall.    502 

of  tongue.  313 

of    uterus,    500 

vessels   of   body,   496 

superficial   and   deep,   498 

M 

Macula  acustica  utricularis,  578 

Mammary  gland.   564 

blood    supply,    564 

nerve   supply.    567 
Manubrium.  23G 
Malar  bone.  ."33 

bone  zygomatic  process  of,  534 

bone   muscles   attached,   534 
Male  organs  of  generation.  564 
Malpighian   tuft,  469 

pyramids,  469 
of  kidney,  468 
Malleus    bone,    574 
Marginal    gyrus,    346 
Masseter  muscle.  52m 
Mastoid  foramen.  554 

antrum,  574 

cells.   57t', 

process,  517 
Meatus   auditorius  internus,   553 
Meat  uses  '  >i  in  »se,  551 
Meckel's    ganglion.    4(14 
Mediastinum  description  of,  460 
Mediastinal   artery,   44s 

pleura.   256 
Median   nerve,  99-101 

muscles  supplied  by,  101 
Medullary  portion  of  kidney,  468 
Medulli  spinal  veins,  486 
Medullary  velum,  437 
Medulla  oblongata  description  of,  359 

oblongata,  357 

fibers  of,  360 

nucleus  of,  360 

oblongata  surfaces  of,  360 
Medulla  veins  of,  488 
Meibomian   glands,    389 
Meissner's  plexus.  322 
Membrane   cochlea,   578 
Membrana  granulosa  of  ovary,  561 

propria   of  ovum,  561 
Membranous  labyrinth  of  ear, 
Membrana  sacciformis.  119 
Membrana  semi-circular  canal,  578 

tympani  blood  supply,  571 

tympani    nerve    supply,    571 

tympani,    571 


INDEX. 


no;, 


Membrana  tensa,    571 
Membrane,   defiinition   of,    405 
serous  description  of,  465 
cutaneous   description    of,    465 
mucous  description  of.  465 
synovial   description   of,    465 
Meningo-rachidian  veins,  486 
Meningeal  artery.  293 
Mesoblast,    331 
Mesentery,    The    466 
Mesenteric  artery,  321 

superior  and  inferior,   326 
plexus,   426 
Metacarpal  bones,  109 

articulations  of,  109 
Metacarpal  bones,  nutrient  artery  of,   109 

arteries,   92 
Metatarsal  arteries,   184 
Metatarsus  bones.    164 

nutrient    artery,    164 
muscles    attached,    164 
Metatarso-phalangeal    articulation,    206 
Metencephalon,    341 
Middle   cerebral   artery,   444 
cervical  ganglion.  422 
commissure,  348 

of  brain,  348-437 
cuneiform    bone,    164 

attachment    of   muscle^.    164 
ear,    568-571 

blood   supply,  573 
nerve  supply,  573 
hemorrhoidal    artery,    172 
mediastinum.    460 
meningeal   artery,   296 
radio-ulnar  articulation,  78 
vesical    artery,    173 
Midriff,    234 
Mitral    valve.    242 
Moderator  band  of  heart.  242 
Mons  veneris,  562 

Motor   fibers    sympathetic,    431 

impulses  indirect   route.  435 
direct   route.  435 

tracts   of.    435 

oculi    nerve,    439 
paralyses  of,  390 

oculi    nerve,    :;s9-368 
Mouth,  ducts  of.  315 

lymphatics  of.  505 
Middle  constrictor  muscle,  551 
Muscular  accessorius,  274 
Musculo  cutaneous  muscles  supplied  by,  102 

spiral  muscles  supplied  by,  103 
Multifidus  spinse  muscle,  276 
Musculi  pectinati,  2  10 
Muscles  of  abdomen,    160 

abductor  hallucis,  1 58 
minimi  digiti,  158 
minimi    digiti,    1 1 3 

accelerator   urine,    192 

addud or  brevis,   I  hi 

longus.    140 

maerous,    140 


Muscle,  adductor  obliquus  hallucis.  15s 

obliquus  pollicis,    112 

pollicis,  111 

t  ransA  ei  sue  hallucis,  160 

transversus   pollicis,    112 
anconeus,   87 
:int  itragicus,  570 
aryetnoideus,  -'.'._' 
arj  teno-epiglottideus,    J~>- 
of  at  hi-.  260 
attachments  of    24 
of  axis,  Jo  i 
asygos   uvulae,   549 
of  hack.   27(1 
bicep-.  5s- 1  Hi 
biventer  cervicis,  27  1 
brachialis  anticus,  79 
buccinator,   540 
cervicalis  ascendens,  -'7  1 
chondro-glossus,  550 
of  coccyx,    134 
coccygeus,  491 
coniplexu-.    274 
i ipressor   nasi,   539 

urethras,    192 

urethra.  403 
coraco-brachudi-.   58 
corrugator  cut i-  ani,  190 

supercilii, 
cremastei .  46 1 
crico-arytenoideus,  251 

thyroid,  251 
crureus,  138 
deltoid,    13 
depressor  alse  nasi,  539 

anguli  oris,  5  15 

labii  inferior].-,  54  1 
dilator  uares  posterior,  5 10 
digastric,  521 
dorsal    interossei,    160-1 14 
ear,    570 
erector  clitoridis,  493 

penis,   192 

spinse,    272 
of  esophagus,  :;i 7 

ethmoid  hone  of.  526 

extensor  brevis  digitorum,   157 

pollicis, 

carpi  radialis  ho-,  ioi    85 

carpi  radialis  longioi .  85 

coccygis,   278 

communis  digitoi  um    B5 

iadicis,    '.'l 

longus  digitorum,   1 52 

longus  pollicis,  91 

minimi  digiti    s7 
longus   hallucis,    h">i 
pollicis,    m 

profundus  digitorum 

sublimis  din 
forced  inspiratioi 

expiral  ion 
frontal  bone  ol 
iifin  in  - 


606 


INDEX. 


Muscle,  gemellus  inferior,  ill 

superior.    1  I  I 
genio-hyoideus,   .544 

byo-glossus,  S  I  I 
gluteus  maximus,  1  1 1 

medius,   1  1 1 

niininms,    143 
gracili 
,,f  band,  L06 

helicis    major.    570 

minor.    570 
of  hyoid  hone.  550 
hyo-glossus,  550 
iliacus,    135 
ilio-costalis,  273 
Lnfracostals,    158 
inferior  lingualis,  551 
of  inferior  maxillary  bone,  543 

oblique.  538 

rectus,   530 
infraspinatus,  55 

internal   cremasteric,   567 

intercostal-.    158 

pterygoid,  529 

rectus,   531 
inter  spinales,   278 
internal  sphincter  ani,  490 
intertransversales,  278 
ischio-rectal  region,  490 
lachrymal   hone.   532 
of  larynx,  250 
latissimus  dorsi,  52 
levatores  cost  arum,  459 

levator    ani.    4(H) 

aneuli   oris,   539 

anptili  scapulas,  54 

lahii  inferioris,  545 

lahii  superioris  alseque  nasi.  539 
proprius,  540-534 

palate,  523 

palpebra    529 
longissimus  dorsi,  27  1 
lumbricales  band, 

foot.   162 
malar  hone.  534 
massetei .  520 
middle  const  i  ictoi .  551 
multifidus  spina-.  27(i 
mylo-hj  oid,  5  1 1 
of  nasal  hone,  .",:',_' 
Dumber  of.  _':; 
obliquus    aurem,    570 

oapitus   superior,   278 
inferior,  280 

externus,    160 

internus,    hil 
obi  urator  externus,  1  1 1 

internus,    i  hi 

occipital  hone-  ..• 

occipito-frontalis,    51  '■'■ 

omo-hyoid,  59 

opponens  minimi  digiti,   1  13 

pollicis,   1  12 
orbicularis  oris,   540 


Muscle,  orbicularis  palpebrarum,    508 
.if  orbit,  372-370-529 

palate  bone.  547 

parietal  bone    51(1 
palmar  interossei,  1 14 
palmaris  brevis,    1 13 

longus,  81 
pectineus.   13s 
pectoralis   major.   41 

minor,  50 
of  perineum,  male,  491 

female.    192 
peroneus  brevis,   157 

longus.    156 

tertius.    153 
of  pharynx,  314 
plantari.-.   154 
plantar     inten  i.-ci.     160 

platysma  myoides,  545 
popliteus,  154 

principles  of,   24 
pronator  radii   teres,   79 

quadrat  us,   84 
psoas  magnus.  134 

parvus,  134 
of  pubis.    129 
pyramidalis,  463 
pyriformis.    143 
quadrat  us  femoris,  144 

lumhorum.    4f>4 
rectus  capitus  amicus  major,  514 
minor,    514 

posticus  major,  278 
minor,    278 
lateralis,    514 

abdominus,  463 

femoris,    136 
of  rectum,  324 
ret  rahens   aurem,   522 
rhomboideus  minor,  55 
rot  at  ores  spinas,  276 
of  sacrum.   133 
serratus   magnus,  54 

posticus  inferior,  272 
superior,   271 
sartorius,    135 
of  scapulae,  50 
semimembranosus,    1  17 
semitendinosus,    14(> 
semispinalis    dorsi,    276 

colli,   276 
stylo-pharyngeus,    522 
of   -oft    palate,   316 
soleus,    153 

splenius  capitis  and  colli.  272 
sphenoid  hone,  528 
s|  ihincter  vagina,  493 
spinalis    dorsi,    i»74 
stapedius,  523 
sterno-cleido-ma&toid,  4 

hyoid.  40 

thyroid,  41 
stylo-glossus,    522 

hyoid,    522 


INDIA. 


60* 


Muscle,  subcrureus,  138 
subclavius.  4_' 
subanconeus.  79 
supinator  brevis,   88 

longus,  84 
subscapularis,    56 
superior  constrictor.   .515 
<>f  superior  maxillary  bone,  538 

oblique,  530 

rectus.   530 
supraspinales,  276 
supraspin&tus,   55 
of  temporal  bone.  520 
temporal.   520-508 
tensor  vaginae  femoris,  135 
teres   major.   56 

minor,  56 
tensor  tarsi.  532 

tympani,  523 

palati.    523 
of  thorax,   457 
thyro-arytenoideus,  252 

epiglottideus,   252 
thyro-hyoid,    550 
tibialis  anticus.  152 

posticus,    156 
of  tongue.  311 
trachelo-mastoid.  274 
tragicu.-.    570 
triceps.  50 

triangularis  sterni.   458 
transversalis    colli,    -74 
transversalis,   462 
transversus  perinaei,  491-492 

aurem.  570 
trapezius.  45 
vastus  externus.   137 

internus,    137 
zygomaticus    major.    535 

minor.  535 
extensor  ossis  metacarpi  pollicis,  88 

proprius  ballucis,  L52 
external    intercosttl    457 

rectus,    531 

sphincter  ani,  490 

pterygoid,  529 
of  eye.  529 
of  fern  ui-.    l".i  I 
flexor    accessorius,    161 

carpi  radialis,  .Si 

ulnaris,    81 

brevi-  minimi  digiti.  1 13 

(ligitorum.  158 

nallucis,  162 

pollicis,   1  12 

longus   digitorum,    156 
and  joint    sensation,    133 
Musculo  phrenic  artery,   1 19 
Mucous  membrane,  description  of.    165 
Myelon,  341 

Mylo-hj  oid  muscle,  544 
Myology,  definition  of.  17 
Myopia.   374 


N 

NasaJ   arterj 
bone,  531 

muscles  attached 
cresl 

-pin-.  5:;s-:,ii7 
fossae,  552 
ner\  1 

notch.    507 
-lit.    52.-, 

meatuses  of,  551 

Navicular    bone,    163 

attachment  of  muscles,   163 
Neck.  Lymphatics  of,  5111 
lymph  node-  of,  505 
Nelaton's  line.    196 
Nervi-molle-.     l.'l 
Nerve  abducent .  392 
anterior  crural,   210 
interosseus,    KM 
tibial,  218 
atlas  of,  264 
axis  of,  264 
auditory.    579 
Vuerbach's  plexus,  322 
auriculo-temporal,  402 

buccal.    402 

centers  definition  ot.  27 
cervical,   3' 

plexus,   304 
circumflex,  99 
coccygeal  plexus,  218 
communicans  hypoglossi,  306 

cranial.   364 

origin   of,   364 
cutaneous,  214 
dental,  398 
desci  ipl  ion  of,  26 

roots  ol     27 
dorsal,  35 
external  cutaneous,  21 

■  boracic,  98 

plantar.  216 
to  lac-      398 
facial.  4(17 
genii  o-crural,  -'1  8 
glosso-pharyngeal,    I  in 

it   auricular 

sciatic,  215 

superficial  petrosal    mi 
to  hip-joinl .  212 
ilio-hypogastric 
ilio-ihguinal,  278 
inferior  dental.   102 

gluteal,  21  I 

maxillai  j .  399 
internal  cutaneous,  K  6 

1  tioracic,  '.  9 

plantai    216 
to  kidney,    I7n 
labial 
of  Lancisi 
lame,  deep  pel  rosal.  \0 1 


608 


INDEX. 


Nerve,  lesser  internal  cutaneous,  106 
lingual,  402-411 
Song   sii'  scapular.  99 
lumbar    L'08 

plexus,   208 
nie.lian,    99-101 
Meissner's  plexus,  322 
motor  definition  of,  27 
motor  oculi,  389-368 
musculo-spinal,    103 
nasal,    390 

obturator.  L'12 

obturator  accessory,  212 
ophthalmic,  394 

optic,  366 

patellar    plexus,    210 

palpebral,  398 

perforating  cutaneous,  214 

peritoneum  to,  467 

peroneal,     181-217 

pharyngeal,  410 

plexus,    315 
phrenic,  306 
post-auricular,  408 
posterior  interosseous,   105 

thoracic,  98 

tibial,  216 
popliteal,   180 
principles  of,  26 
pudendal,   214 
pudic,  214 
pneumogastric,  1 1 1 
radial,    105 

recurrent  laryngeal,  414 
Sacro-iliac   articulation, 
sacral   plexus,   212 
sacro-vertebra!  articulation,  280 
sensory  definition  of,  27 
small  occipital,  305-301 

sciatic,   214 
splanchnics,  423 
spinal   accessory,   416 

subsartorial  plexus,  212 

subscapular,    99 
suboccipital.  298-300 
suprascapular.    "IN 

superior  gluteal,  213 

maxillary.  396 

sympathetic,  418 
temporal  deep,  400 
tongue  of,  31 1 

tonsillar.   Ill 

t  r:in-\  erse  cen  ical,  -* ;  <  *  *  v 
Nerve,  trochlear,  368  391 
trifacial,    :'.!•_' 

tubular   prolongations   of,   332 

twelfth  cranial.    117 

t  \  mpanic,   HO 

to    ureter.    471 

visceral  blanch.'-  of  sacral  plexus,  213 

Wrisberg,   km; 
Nrr\  on-  system,  3  \0 
Neuroglia,  331 

Neuron,  341 


Neuroretinitis,  373 
Neurology,  definition  of,   17 
Neuron   system,   433 
Nodes  internal  mammary,  562 

lymphatic, 
Ninth  nerve,  410 
Neucleus  ambiguus,  410 

emboliformis,   361 

fastigii,  362 

globosiis,  362 


Obex  of  brain,  443 
Obliquus  aurem  muscle,  570 

capitus  superior  muscle,  278 

inferior  muscle,  280 
externus  muscle,  460 
internus  muscle,  461 
Obliterated  processes  vaginalis,  567 
Obturator  accessory  nerve,  212 
artery,    172 
externus   muscle,    144 
foramen,    131 
fascia,    495 
internus  muscle,   143 
nerve,  212 
Occipital  artery,  293 
Occipito-atlantal  ligaments,  260-26] 
Occipital  bone,  511 
muscle  of,  513 
ossification   of,    513 
basilar  process  of,  512 
lobe,   344 
sinus,  489 
triangle,  282 
vein,   487-481 
Occipito-frontalis  muscle,  513 
Odontoid   ligaments,   264 
(Esophageal  artery,  449-450 
(Esophagus  lymphatics  of,  503 

nerves  of,  416 
Olecranon  process,  75 
Olfactory  bulb,  347-365 
foramina,  553 
nerve,    439 
tracts,    365-437 
Olfactory  tracts  arachnoid  of,  366 
dura  mater  of,  366 
pia   mater  of,   366 
roots  of,  365 
Olivary  nucleus  of  pons,  363 
Omo-hyoid    muscle,   59 
Ophthalmic  artery,  368-444-383 
branches  of,  383 
ganglion,  394-403 
nerve,     394 
Optic  commissure.  357-366-437 
foramen ,  368-553-52S 
nerve,  366-439 

lesions  of,  367 
radiations,    367 
thalamus,  347 
thalami,   352 


[NDEX. 


609 


Optic    tracts,   367 

coverings  of,  368 
Opponens  minimi  digiti  muscle,  113 

pollicis  muscle.  112 
Orbicularis  oris  muscle.  540 

palpebrarum   muscle,    508 
Orbit,   description  of,   368 

angles  of,  370 

bones  of,  368 

boundaries  of,  370 

foramina  of,  369 

floor  of,  369 

lymphatics  of,  504 

muscles   of,   372-376 
Organ  of  corti,  577 

generation  male,  564 
hearing,  568 
Os  calis  bone,   162 

Os  calcis.  attachment  of  muscles,  162 
Osmatic  animals,  365 
Osteology,  definition  of,  17 
Otic  ganglion,  405 
Ovaries,  560 
Ovary,  blood  supply  of,  561 

nerve  supply  of,  561 

corpus  luteum  of,  561 

coats  of,  561 

Graafian  follicles  of,  .561 

ligaments  of,  560 

location  of,  562 

normal   position  of,   561 

stroma  of.  .~>t;i 
Ovarian  arteries.  457 

veins.  190 
Ovum,  description  of.  561 


Palate  bone,  538-547 
borders   of,    548 
surfaces  of,  548 
muscles  attached,  549 
nutrient    artery,   549 
articulation  of,  549 

Palmaris  brevis  muscle,  113 

Palmar  fascia,   116 

Palmar  interossci   arteries,  HI 
muscles,    1 14 

Palmaris  longus  muscles,  81 

Palmar   recurrent    arteries,   95 

Palpebral    nerve,   398 
Pampiniform    plexus,    190 

Pancreas   326 

blood  supply  of,  326 
nerve  supply  of,  326 

lymphatic-   of,   326 
Pancreatica'  parvae  arterj  .   153 

magna  artery,  453 
Papillae  of  tongue,  31 1 
Papillitis.   373 
Paradidymis,   568 
Parenchymatous  goitre,  246 
Pa>ietal  bone,  articulation  of,  510 
description  of,  olid 


gyri.   346 
lobe.  :;  1 1 

bone  muscle  of,  Mo 
Parietal  bone,  nutrienl  artery  of,  500 
ossification,  510 
to-occipital  fissun 
Paroophoroi 
Parosmia,  365 
Patellar  plexus,  210 

ah-    major   muscle,     I  1 
minor  muscle,    II 
Pectineus   muscle,    I  :^ 
Peduncles  of  cerebellum,  362 
brain.  .;:.  I 

258 
Pelvis.    131 

dimensions  of.   i:;i 
Pelvic   fascia,    195 
Pelvis  female.   L32 
Perforating  cutaneous  nerve,  211 
Peni-. 

bl I  supply,  566 

dartos    565 

a,  565 
corpus  spongiosum,  565 
Penis  nerve  supplj  .  566 
Perineum 

central  tendon  of,    195 

fascia  of,    19  1 

muscles   of   female,   4<I2 
of  male.    l!l| 

-i  met  ure-    iii.     195 

triangular  ligament   of,   495 
Paricardium,    238 
Pericardiac  arterj  .    I  18-450 
Peroneal    artery,    186 
Peroneu-  brevis  muscle,  157 

longus  muscle,    156 

Peroneal   nei  \  e,  217-181 

Peroneus  ten  in-  muscle,   L53 
Peril  isteum  fund  ion  of,  19 
Peripheral    system 
Peritoneum  bl I  supply  of,  4i>7 

description  of,    165 

fund  ions  of,   166 
.  166 
....  i      166 

ligaments  formed  by,  466 

nerve  supplj   of,    Pi? 

parietal  laj  ei  i  ' .   165 

-t  i  net  urea  <-<>\  ered  bj 

\  isceral  laj  ei   ol .    165 
Pel i on-  ganglion,  no 

porl  ion  tempi  n  al  bone,  517 
Peyer's  patches,  320 
Phalanges  bones  attachmenl  of  muaclaa    164 

nut rient    arterj  .    164 
Pharynx,  313 

boundari f,  313 

openings  in 
I  'hi  i  ynx,  blood  supply,  .'(15 

in  i  -,  e  supp 

lymphat  ii 

muscles  of.  31  I 


610 


INDEX. 


Pharyngeal   nerve,  410 
nerve  of  vagus,   II  1 

plexus,  •';!  i 
Pharygneal  tonsil,  313 
Phrenic  artery  of  aorta,  452 

artery,    I L8 

hernia,    174 

nerve,    306 

plexus,    125 

vein-.   190 

l'ia  mater  of  brain,  34 1 

of  cord,  333 
Pillar-  of   iri-.   380 
Pineal   gland,    353 
Pinna  "f  ear,  569 
Pirogoff's  amputation,   194 
Placenta,  3  l 

Plantar  digital  artery,  184 
Plantar  fascia,  223 

Plate,    161 
Plantaris   muscle,    154 

interossei  muscle,  Hiit 
l'lai  ysma  mj  oides  muscle,  5  15 
Plexus  bi  achial,  3  i 

cei  \  Leal,  35 

coccygeal,   35 

definition   of,   •'■! 

-anal.    35 
Pleura.  256 

nerve  supply  of,  256 

blood  supply  of,  256 
Pneumogastric  accessorj    part.  412 

connect  tons  of,   111 

di-t ribul ion  of,   1 1  I 

left .     Ill 
nerve.    111-41 1 

cardiac  branches,  1 16 

pulmonary  branches,    1 L6 

right,  412 
Pocularis   sinus,    17:'. 
Pons,  362 

construction    of,    363 

cru;-  cerebri,  363 

nei  \  e-  of,  363 

varolii,    357-362-437 

veins  of,  188 
Popliteal  artery,   17(1-180 

branches  of,  1  M 
Popliteus  muscle,  154 

space,   180 

vein,     L92-180 

Portal  system,  326-  is  I 

vein,   324   is:,  mo 
Po  tei  i'  'i  annulai  Ligament .  1 16 

am iculai    nei  v e,  408 
vein,    181 

cai  pal   art< 

cardiac  \  ein,  is.'i 

cerebral  artery,  1 l*> 

circumflex  arterj  .  65 

communicat  ing  arterj  . 

commissure,  348 

commissure  of  brain,  -;is  137 

ci indj  I' »id  foramen,  55  I 


Posterior  interosseous  nerve,  105 

ethmoidal  artery,  384 

ethmoidal  foramen,  553 

interosseous    artery,    95 
Posterior  external  jugular  vein,  481 

ligament,  62 

mediastinum,  460 

mediastinal  arteries,  450 
nodes,  502 

nerve  root,  333 

perforating  arteries,  186 

perforated   space  of  brain,  441 

scapula  artery,  1 10 

spinal  arteries.  ■  Y-'<7 

tibial  artery,  180-185 
relation  of,    186 

thoracic  nerve,  98 

tibial  nerve,  216 
vein.   MIL' 
recurrent  artery,  782 

ulna    reeurre.  I    artel  \  .   95 
Pouch  of  Douglas,  558 
Poupart  's  ligament .  477 
Preputium  clitoridis,  563 
Presbyopia,  375 

Prevertebral  plexus  of  symphatic,    123 
Princeps  pollicis  artery,  93 
Processus-e-cerebello-ad-te-te-.  354-437 

cochleariformis,   520 
Profunda  artery,   176-180 

femora]  artery  branches  of.  178 

artery  perforating  branches  of.  180 
Pronator  quadratus  muscle.  84 

radii  teres  muscle,  79 
Prosencephalon,  341 

Prostate  gland.  5IJ4-474 

Prostat  ie  sinus,  473 

Pseudocele,  358 

Psoas  magnus  muscle,   134 

parvus  muscle.  134 
Pterygoid  artery,  297 

processes,  528 
Pterygo-maxillary   fissure,  555 

palatine   artery,   298 
Pubic  artery,   176 

bone.    128-127 

muscles  of,   129 

attached.    128 
lie!  \  e.  214 

Pudendal   nerve,  214 
Pulmonary  artery,  284 

nerves,    110 
Pulsating  goitre.  2  16 
Pulvinar,  352 
l'upillo-dilator  fibers,  431 

Pyloric,  318 

artery,    153 

glands,  318 
Pyramids  of  I  errein,  468 
Pyramidalis  muscle,  463 
Pyramidal  tracts.  334 
Idier-  of,  435 

Pyriformis  muscle,  1  13 


INDEX, 


611 


Q 

Quadratus  femoris  muscle.  144 

Quadrate  gyrus,  346 

Quadratus  lumborum  muscle,    164 

Quadrilateral  space,  77 
Question  review.   120 

lower  extremities.   224 


Right  innominate  coronary  vein. 
Rivinian  foramen,  .">7 1 

duel 

Rhinencephaion,  34J 
Rhomboideus  minor  mu- 
:   lungs,  257 
res  spins  i 
Roux's  amputation,    194 
Ruga  of  stomach 
Rule  oi 


Radial  nerve,   10.5 

artery  relations  of,  95 
branches  of,   92 
muscular  branches  of,  92-95 
recurrent    artery,   92 
region  forearm.  <>9 
Radialis  indicis  artery.  94 
Radius  description  of,  72 
borders  of,  72 
muscles  attached.  75 
perimeter  of,  73 
Radio-ulnar  articulation.  79 
blood  supply  of,  79 
nerve  supply  of,  79 
Ramus  of  ischium.  130 
Ranine  artery,  291 
Receptaculum  chyli,  497 
Recto-vesical   fascia,   495 
Rectus  capitis  posticus  major  muscle,  278 
minor  muscle.  27s 
anticu-  major  muscle,  514 

minor    muscle,    514 
lateralis    muscle.    514 
abdominis  muscle,  163 
femoris  muscle,  136 
Rectum,    320 

description  of,  324 
muscles  of,  324 
lymphatic-  of,  500 
Recurrent  laryngeal  nerve.  414 
Keflex  impulses.   437 
Refracting  media  of  eye,  378 
Renal  arteries,  456 
lymphatic-.    17! 
plexus,  425 
veins,  190 
Residua]  air,  258 
e  air,  258 
Restiform  body,  360 
liber-  of,   364 
Respiratory  center,  359 
Reticula  of  spinal  cord,  333 
Retina,  376 

description   of,   378 
layers  "i 
Retinal  hyperesthesia,  374 
Retrobulbar  neuritis,  37.'') 
Retrahens  aurem  muscle    322 
Review  iiuesiionb,  lowei  extremity,  22  1 

upper  exl  remity,  120 
Rib,  firsl  and  second,  270 

descripti  m  of,  268 
Right   Innominate  vein,    182 


Saccule  •  if  i 
Sacral  groove,   132 

sympathetii 

plexus,  213 

plexus  vi-ceral  branch. 

Sacro-vertebral  articulation, 

.Sacrum.  132 

base  of,  132 

articulation.   133 

ate,    133 

muscles  attached,  133 

ossification  of,  133 
Salivary    center, 

glands, 

parotid,  579 

submaxillary.    ,~>su 

sublingual,   580 
Saphenous  opening,  220 

veins.  192 
Sartorius  muscles,   135 
Scapula  description  of.   15 

articulation   of.    Is 

ligament-    o        Is 

muscles  of,  50 
Scalp  lympha 
Scarpa'-  foramina,  538 
Scarpa'-  triangle,  176 
Schneiderian  membrane 
Sciatic   artery,    17  1 
Sclerotic   coat    of   .  \ .      376 

description  of 
Scrotum.    568 
Second   ner\ . 
Segment-  of  cord 
Semicircular   canal    of   , 
Semilunar  fibro-cartilages,   200 

valves,   241 
Semimembranosus  muscle,  l  17 
endinosis  muscle,   i  16 

Semi-pinali-  colli  muscll 

dor-i   muscle,   276 

Sen-  iry,   council 

impulses,  routi 
Septum  lucidun 

-. 

p..-l  icu-  SU| 

i.s 

muscle*  af 

Se\  enl  h 


612 


INDEX. 


Sharpnell's  membrane,  571 
Shoulder  join! .    18 
ligaments 

1)1 1  supply  of,  18 

net  \  e  supply  nf,  48 
Small  meningeal  arterj  .  297 
occipital  nerve,  301-305 
sciatic  nen  e,  21  I 
Smell,  center  of,  36  I 
diseases  of,  365 
Sinus,  definition  of,  17 
nous,    189 
circular,  189 
Sinuses  of  dura  mater,  488 
inferior  longitudinal,  489 
petrosal  490 
!.    189 
Sinus  of  larj  ax,  250 
of  Morgagni,  31  5 
occipital,  489 
rhomboidalis,  33  I 
straight,    489 
-upei  ii  ii   lmiirit  udinal,  4SX 

petrosal,  189 
torcular  Herophili,  489 
transverse,  490 
valsalva  of,  242 
Sigmoid  artery,  455 
gyrus,  346 
flexure,  320 

Sixth  nerve,  392 

Skej  '-  amputation,  19  I 
Skin  of  back,  280 
Skull,  base  foramina  of,  552 
Sofl   palate,  315 

muscles  of,  3]  6 

Solar  plexus,    I-  I 

function  of.    131 
Solitary  gland,  321 
Soleus  muscle,  L53 
Sounds  of  hear;.  246 

matic  artery.  576-456 

cord,  566 
plexus,    125 
veins,  576-190 
Spheno-maxillary  artery,  297 
fossa,  555 
B    lire    555 
Spheno  palat  tne  artery,  298 

branches  of,  297 
Sphenoidal  fissure,  553  528 
Sphenoid   bone,   526 

nutrient   ai  terj    of,  529 
foi  amina  i  if,  527 
t  i — «ii  <  s  of,  528 
lessei  wings  of,  528 
muscles  ai  tached,  528 
orbital  surface  of,  527 
pterygoid  processes  of,  528 

tin  lunate, 1    bom 

wings  of,  527 
Sphincter  vagina   muscle,    193 
Spina  bifida 
Spina]  accessor}    nei  ve,    H 6-441 


Spinal  canal,  133 

column  fractures  of,  334 
veins   of,    486 
Spinal  cord,  330 

diseases  of,  334 
ascending  fibers  of,  335 
descending  fibers,   335 
blood  supply,  336 
enlargements  of,  330 
fissures  of,  335 
gray  matter  of,  336 
membranes  of,   332 
Begments  of,  337 
veins  of,  486 
white  matter  of,  330 
Spinal  nerve  first,  298 
Spinalis  dorsi  muscle,  274 
Spinous  process  of  vertebra;,  258 

Spiral   canal    of   car.   578 

Splanchnology  definition  of,  17 
Splanchnic    nerve   greater,   423 
lesser,    123 

Spleen,   248 

relations  of,  248 
blood  supply  of,  248 
nerve  supply  of,  248 
dimensions  of,  24S 
lymphatics  of,  501 

Splenic    artery,    327-453 
plexus,    125 

Splenic   vein,  484 

Splenius  capiti:    muscle,  272 
colli  muscle,  272 

Stapes  bone,  574 

Stapedius  muscle.  523 

Steno  s  duct .  315 

Stenson  foramina,  538 

Stephanion,  555 

Sterno-pericardial,  238 

clavicular  articulation,  38 
cleido-mastoid   muscle,   40 

hyoid  muscle.  4 

thyroid  muscie,   11 
sternal    arteries,    448 
Sternum,   236 

muscles  attached,  237 
Stomach,  318 

blood  supply  of,  318 

nerve  supply  of,  318 

muscles  of,  318 

relations  of,   319 

glands   of,   318 

lymphatics  of,   501 
Stroma  of  ovary,  561 
Straight    sinus,    189 
Strangulated    hernia,     175 
Structures  of  heart,  243 
Styloglossus    muscle,    51':' 

hyoid    muscle,    522 

pharyngeus  muscle,  522 
Styloid  process,  519 
Subanconeus  muscle,  79 
Subarachnoid   spaces,   335 
Subastragaloid   amputation,    194 


[NDEX. 


613 


Subscapular   nerve-.    99 
Subclavian    artery,    4-1.5 

relations  of  44t>-  1 17 
vein,   482 

triangle,  282 
Subcrureus  muscle,    138 
Subdural  space.  332 
Subflava   ligament,   266 
Submaxillary    ganglion,    405 
Submaxillary   triangle,    282 
Submental    artery.    292 
Suboccipital    nerve,    300-298 

triangle.    282 
Subclaviu>  muscle,   12 
Subscapular^    muscle,    56 
Subscapular    artery.    65 
Subsartorial  plexus,  212 
Substantia  gelatinosa  rolandi,  330 
Sulci.  342-343 

Suprahyoid  lymphatics.  504 
Suprarenal    artery.    456 

capsules.   248 

blood   supply   of,   248 
nerve   supply   of.   249 

vein.   190 
Suspensory  ligament  of  ovary,  561 
Superficiali<  volae  artery.  92 
Suprascapular  artery,  449 

nerve,  98 
Supraorbital  artery,  384 

nerve.    394 

notch.  372-506 

vein,   487-480 
Suprarenal    plexus. 
Supratrochlear   nerve     394 
Superficial  circumflex  iliac  artery ■  178 
Superficial  cervical   artery.   449 

descending    artery.    288 

external   pudic   artery,    178 

epigastric  artery.   178 

femoral  artery    176 

lymphatic    vessels.    498 

palmar    arch.    96 

temporal    artery.    29  1 
Superior  maxillary   nerve,   396 

cervical  ganglion.  421 
branches  of,  421 

constrictor    muscle,    515 

external  angle  of  orbit,  370 

epigastric  artery,  449 

fibular   artery,    182 

gluteal  nerve,  213 

hemorrhoidal  artery,  456 

intercostal  artery,  449 

laryngeal   artery,   288 

longitudinal    sinus,    488 

maxillary   bone,   535 
areolar  pr< » 

antrum   of   Highmore,   537 
lachrymal    groove,    537 
surfaces  of,  537 
palate  proce->  of,  53S 
muscles  attached,  538 

mediastinum,    460 


mesentery  artery,  454 
nteric    vein,    484 
plexus 
oblique  muscle. 
perforating  arte 
petrosal   sinus,    189 
profunda  artery,  66 
radio  ulnar  articulation,  7^ 
rectus    in1. 
thoracic  artery,   62 
thyroid  artery,  288 
vena 

vesica]   artery     17_' 
Supinator    brevis    muscle,    sv 

longus  mu- 
Supraspinous  ligament  - 
Supraspinatus   muscle,  55 
Supraspinales  muscle,   - 
Sura'    arteries,    182 
Suspensory  Ligament  ol  e\e    378 
Sylvian  fis-ure.  343 
Syme     amputate  ".   '94 
-'ympathetic  neM       llv 

acceleratore  to  lieart.  431 
cervical    region,  420 
dorsal,  420 
lumbar,  420 
sacral,    120 
development   of,    12 
gross  anatomy  of,  431 
lumbar,  423 
lumbar,  423 
sacral,    423 

motor  libers  to  eye.     143 
thoracic   ganglia,    !-'_' 
Synarthrosis  divisions  of,  25 
Syndesmology  definition  of,  17 
Synovia]  membrane  description  of,  405 
Systole   of   heart.   245 


Taenia  semicircularis  of  brain,  350-437 

Bemicircularis,  356-352 
Talepes  description  of.  l!1-' 
calcaueous,   194 
arcuatus.    194 
valgus,   I'M 
varus,  194 
equinus,    194 
plantus,    194 
Tarsal  plate-  of  li 
Tarsus,  metatarsus  joints,  206 

joints,  ligament  -  of,  20  1 
reeth,  descirption  of,  309 
310 
nerves  of,  :>b> 
Tegmenl  um  of  pon 
najor  muscli 
Tela  choroide 

inferior  of  brain,   1 1 1 
ro-maxillarj   vein,   Is" 
sphenoidal    fissure,   3 1 1 
lobe,  344 


614 


INDEX. 


Temporal  artery  deep,  297 
bone,  51b 

articulation  of,  520 

auditory   meatus  of,   517 

inferior    surface,    519 

muscles  of,  520 

mastoid  process  of,  511 

nutrient   artery  of,  520 

processus  cochleariformis,  520 

process  of.  519 

petrous    portion,    517 

zygomatic    process,    516 
Temporal    gyri, 
fossa,  554 
muscle,  520-508 
nerves   ileep,   400 

ridges,   507 
veins.  4S7-4S0 
Tendino-trochanteric    band,    196 

Tendon,  definition  of.  17 
Tenth  nerve.  41 1 
Tentorium  cerebelli,  360 
Tensor    palati    muscle,    523 
tarsi  muscle,  532 
tympani   muscle,  523 
vagina-  fenioris  muscle,  135 
Testicle-.   567 

covering;  of,  567 
lobules  of,  568 
lymphatics   of.   501 
Thalamencephalon.  341 
The  mesentery,  466 
Thigh  superficial  fascia,  218 
Third  nerve,  390 
ventricle,  358 

boundaries   of,    437 
Thoracic  aorta.  451 

branches  of.   450 
duct,  496 

coats  of,  497 
relation  of,  497 
ganglia    sympathetic,    422 
wall  lymphatic  of,  512 
Throat,  316 

Thorax,  description  of,  232 
muscles  of,  457 
openings  of,  232 
Thorax    structures   passing   through    superior   open- 
ing, 232 
Thymic  vessels.  503 
Thymus  gland,  248 

blood    supply,    248 
nerve    supply,    248 
Thyroid  gland,  246 

diseases  of,  246 
blood   supply  of.   _'17 
nerve   supply   of,   247 
Thyroid    axis.    449 
Thyro-arytenoid  ligament,  250 
arytenoideus  muscle,  252 
epiglottideus   muscle,   252 
hyoid    muscle,    550 
Tibia,  bone,   166 

nutrient  artery,  168 


Tibia,  attachment  of  muscles,  168 
Tibialis   anticus   muscle,    152 

posticus  muscle,   156 
Tibio-fibular  joint  superior.  202 
Tidal  air  of  lungs,  258 
Tongue  nerves  of.   311 
Tongue,  311 

muscles  of.  311 

papilla?,  311 

lymph  vessels  of,  313 

blood  supply  of,  313 
Tonsils  description  of,  315 
Tonsillar   artery,   291 

nerve,    411 
Torcular  Herophili,  489 
Trachea.    254 

blood   supply   of.   254 

nerve   supply   of,   254 
Tracheal    artery,    449 
Tracts   of    cord.    433 
Tragicus   muscle,   570 
Tragus  of  ear   570 
Trachelo-mastoid  muscle,  274 
Tranquil  inspiration,  236 
Trapezius   muscle.   45 
Transversalis  colli  artery.  449 
Transversalis    colli    muscle.    274 

muscle,  462 
Transversus  aurem  muscle.  570 

perimei  muscle,  491-492 
Transverse    aorta,    284 

commissure  of  brain,  437-339 

cervical  nerve,   306 

fissure  of  brain,  343 

ligament,   196 
of  atlas.  262 

process  of  vertebra?.   258 

-inus,  490 
Triangles  of  neck,  280 
Triangularis   sterni   muscle,   458 
Triangular    ligament.    494-477 
Triceps   muscle,   50 
Tricuspid  valve  of  heart.  241 
Trigonum  hypoglossi  of  brain.  443 
Trifacial  nerve,  392-439 
Trochlear  nerve.  391-439-368 
Trophic    centers,    334 
Tuber  annulare,  347 

cinereum  of  brain,  441 
Tubercle  of  Lower,  240 
Tubercula    quadrigemina,    347 
Tuberosity  of  rib,  268 
Tubes   of   Ferrein,   470 
Turbinated  bones  sphenoidal,  528 
Turbinated  processes  of  ethmoid  bone,  525 
Tubo-ovarian,  561 
Tubuli  seminiferi.  568 
Tuberculum  acusticum  of  brain,  443 
Tunica  fibrosa  of  ovary.  561 

propria  of  ovary,  561 

vaginalis,  567 
Twelfth   cranial   nerve,   417 
Tympanic  artery.  295 

membrane,   571 


INDEX. 


lil/i 


Tympanic  nerve,  410 
walls  of,  573 

u 

Ulnar   artery,   95 

branches  of,  95 
relations  of,  96 

nerve  muscles  supplied  by,  102 
Ulna,  description  of,  75 

anterior  posterior  borders  of,  76 

muscles   of,   77 

nutrient  artery  of,  77 

olecranon  process  of,  75 
Umbilical    arteries,    472 

hernia,   475 

coverings  of,  478 

regions,  309 

veins,  472 
Umbo  of  tympani,  571 
Uncinate    gyrus,    346 
Urachus,    471 
Ureter  description  of,  471 

blood  supply  of,  471 

nerve  supply  of.  471 
Urethra,  coats  of,  473 

description   of,   472 

divisions   of,   473 

female,  474 
Urinary  system  organs  of,  469 
Uriniferous  tubules,  468 
Uterine  artery,   174 
Uterus,  557 

dimensions  of,  558 

fundus  of,   558 

ligaments  of,  558-559 

os,  558 

blood  supply  of,   559 

coats  of,  559 

nerve   supply  of,   559 

lymphatics   of,   500 
Utricle  of  ear,  577 
Uvula   vesica,   472 


Vagina,  556 

blood  supply  of  557 
Vaginal  coats  of,  557 
Vagus  nerve,  411 
Vallecula,  361 
Valvular  conniventes,  321 
Valves  of  heart,  241 
location,    246 

of  Vieussens  of  brain,  441 
Vasa  aberrant  ia,  69 

l.n\  ia,  453 

efferentia,  568 

intestini  tenuis,  454 

motor  center,  359 

fibers    to    head,    431 
Vas  aberrans,  567 

deferans,   566 
Vastus  extemus   muscle,    137 


interim-     muscle,    137 
Velum    interpositum,    :;.">l 
Vena  azygos  ma  joi .   183 
minor,    1M 
tertius,    184 
Venae  basis  \ ertebrarun 
Vena   cava    inferior,    188 

superior,    483 
Venae  comil  es  leg,  192 
Galeni,    i^ 
Thebesii,  245  l«6 
Ventricle  of  brain,  3  10 

descripti f,   357 

number  of,  358 
Ventricularis  terminales 
Vermiform   appendix,  ;'._'_' 
Vermis    of   cerebellum,    355 
Vertebra?,  description  of,  258 
cervical,    _'.">s 
coccygeal,  258 
dorsal,   258 
lumbar,  258 
sacral,    258 
peculiarities  of,  259 
Vertebral   artery.   447 

column  hi 1  supply 

nerve  supply  of,  339 
ligament-  of,  266 
vein.  481 
Vesiculse  seminales    567 
Vessels  i  if  liver,  190 
Vestibule    of    ear,    577 
Vestigial  fold  of  Marshall,  238 
Veins  of  abdomen,   186 
angular,    480 
anterior  cardiac,  486 
jugular,   181 
tibial,  192 
axillary.     118-482 
basilar,    188 
of  broad  Ligament ,  190 
bronchial.    Is  I 

cardiac,  2  1 1 
cerebellar,  488 
cerebral,    187 
Venae   corporis    striati,    188 
choroidea,   188 

coat-    of,    30 
coronary  sinus,    186 
cystic,    185 
Veins    deep.    IIS 

cervical,    182 
description  of,  30 
desci  n"  i"" 
of   diploe,    187 
dorsi    spinal,     186 
of  dura  mater,    180 
emissarj      187 
in  t  ii  ioi  head  and 
external    iliac,    186 

.     Is  1 

facial,    160 
femoral, 
frontal    187   180 


616 


INDEX. 


Veins,  gastric,  484 

great    cardiac,    485 

of  heart,  485 

hepatic,  190 

iliac,   188 

inferior   cerebral,    487 

mesenteric.     In  1 
innominate,  482-483 
internal   jugular,   481 

iliac,    188 

mn.Tri1lB.ry,  480 
left    cardiac,   485 
lower   extremity,    192 
lumbar,  188 
of  medulla,  488 
medulli   spinal,  486 
meningo  rachidian,    lsc> 
occipital,    487-481 
ovarian,  190 
phrenic,   190 
of   pun.-,    488 
popliteal,    180-192 
portal,  324-190-485 
posterior  auricular,   481 

cardiac,  485 

tibial,  192 

external   jugular,   481 
pulmonary,  30 
renal,  190 

right  coronary,  486 
saphenous,    192 
subclavian,   482 
spermatic,   190-567 
of  spinal  cord,  486 

column,  486 
-picnic,  484 

superior  mesenteric,  484 
superficial,    117 
supraorbital,  487-480 
suprarenal,    190 
systemic,  30 
temporo-maxillary,  480 
temporal,   480-487 
umbilical,    472-34 
Veins,  valves  of,  32 

vena  cava  inferior,  34 

azygos   major,   483 
minor,    484 
vena  cava  superior,  483 
vena'    corporis    striati.     INN 
choroidea,  488 


Veins,  vense  basis  vertebrarum,  48' 
Galeni,   488 
Thebesii,  486 

vertebral,  481 
Villi,   320 

Visceral  branches  sacral  plexus,  21; 
Viscus  description  of,  309 
Vital  capacity  of  lungs,  258 
Vitreous    humor,    376 
Vicq'cl  azyr  fibers  of,  349 
Vocal   cords,   250 
Vomer  bone,  54(5 

muscle  attached,   547 

nutrient  artery,  547 

w 

Wharton's    duct,    315 

White  line  of  perineum,  495 

rami   communicant es,    429-423 

Wirsung's  duct,  326 

Wolffian  body,  564 

Worm  of  cerebellum,  361 

Wrist-joint,  78 

arteries   of,   92 
joint   ligaments  of,   78 
nerve   supply   of,    78 
synovial  membrane  of,   119 


Xiphoid  appendix,  237 


Y-ligament,  194 
Yellow  cartilage,  250 
eastic  tissue,  26-561 
spot  of  retina,  387 
(macula  lutea), 
Yellow  spot  of  ovary,  561 
(corpus  luteum), 


Zygomatic  fossa,   555 
Zygmaticus   major   muscle,    535 

minor  muscle,   535 
Zygomatic  process  temporal  bone,  516 
proce.-s,  534 


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Laughlin,  William  R 
Anatomy  in  a  nutshell. 

QSU 

L3T^a 

1905 

Laugl 
An 

ilin,  William  R 
atomy  in  a  nutshell. 

QSU 

L3T^a 

1905 

MEDICAL  SCIENCES  LIBRARY 

UNIVERSITY  OF  CALIFORNIA,  IRVINE 
IRVINE,  CALIFORNIA  92664 


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